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The following are some of the "statistical" things I've found about the individual data sets.



Table Legend

The "Iteration Count" is the first iteration that produces a given data set. If there were more than one iteration that produced say a 6 million digit number, I only saved the first one.

The formula I used for the "Iteration / Digit Ratio" is: I/D.

The formula I used for the "Digit Pairs Processed" is: Digits(Iterations+7)/2.

Digit Milestone Iteration Count Iteration / Digit Ratio Digit Pairs Processed
1 Million

2 Million

3 Million

4 Million

5 Million

6 Million

7 Million

8 Million

9 Million

10 Million

11 Million

12 Million

13 Million

14 Million

15 Million

16 Million

17 Million

18 Million

19 Million

20 Million

21 Million

22 Million

23 Million

24 Million

25 Million

26 Million

27 Million

28 Million

29 Million

30 Million

31 Million

32 Million

33 Million

34 Million

35 Million

36 Million

37 Million

38 Million

39 Million

40 Million

41 Million

42 Million

43 Million

44 Million

45 Million

46 Million

47 Million

48 Million

49 Million

50 Million

51 Million

52 Million

53 Million

54 Million

55 Million

56 Million

57 Million

58 Million

59 Million

60 Million

61 Million

62 Million

63 Million

64 Million

65 Million

66 Million

67 Million

68 Million

69 Million

70 Million

71 Million

72 Million

73 Million

74 Million

75 Million

76 Million

77 Million

78 Million

79 Million

80 Million

81 Million

82 Million

83 Million

84 Million

85 Million

86 Million

87 Million

88 Million

89 Million

90 Million

91 Million

92 Million

93 Million

94 Million

95 Million

96 Million

97 Million

98 Million

99 Million

100 Million

101 Million

102 Million

103 Million

104 Million

105 Million

106 Million

107 Million

108 Million

109 Million

110 Million

111 Million

112 Million

113 Million

114 Million

115 Million

116 Million

117 Million

118 Million

119 Million

120 Million

121 Million

122 Million

123 Million

124 Million

125 Million

126 Million

127 Million

128 Million

129 Million

130 Million

131 Million

132 Million

133 Million

134 Million

135 Million

136 Million

137 Million

138 Million

139 Million

140 Million

141 Million

142 Million

143 Million

144 Million

145 Million

146 Million

147 Million

148 Million

149 Million

150 Million

151 Million

152 Million

153 Million

154 Million

155 Million

156 Million

157 Million

158 Million

159 Million

160 Million

161 Million

162 Million

163 Million

164 Million

165 Million

166 Million

167 Million

168 Million

169 Million

170 Million

171 Million

172 Million

173 Million

174 Million

175 Million

176 Million

177 Million

178 Million

179 Million

180 Million

181 Million

182 Million

183 Million

184 Million

185 Million

186 Million

187 Million

188 Million

189 Million

190 Million

191 Million

192 Million

193 Million

194 Million

195 Million

196 Million

197 Million

198 Million

199 Million

200 Million

201 Million

202 Million

203 Million

204 Million

205 Million

206 Million

207 Million

208 Million

209 Million

210 Million

211 Million

212 Million

213 Million

214 Million

215 Million

216 Million

217 Million

218 Million

219 Million

220 Million

221 Million

222 Million

223 Million

224 Million

225 Million

226 Million

227 Million

228 Million

229 Million

230 Million

231 Million

232 Million

233 Million

234 Million

235 Million

2,415,836

4,830,292

7,245,928

9,662,071

12,078,865

14,495,294

16,911,863

19,327,667

21,744,278

24,159,531

26,574,642

28,991,159

31,408,295

33,824,775

36,240,602

38,655,227

41,070,365

43,487,182

45,901,512

48,316,988

50,732,545

53,148,015

55,565,809

57,982,436

60,398,130

62,816,046

65,231,462

67,648,377

70,067,270

72,482,579

74,899,358

77,314,955

79,731,034

82,145,364

84,563,227

86,979,674

89,397,247

91,812,894

94,228,899

96,645,213

99,061,141

101,476,346

103,893,138

106,309,010

108,723,539

111,138,308

113,554,695

115,969,543

118,387,016

120,802,305

123,218,044

125,634,154

128,050,160

130,463,975

132,880,223

135,295,252

137,712,060

140,128,242

142,544,153

144,958,406

147,375,122

149,790,895

152,207,835

154,623,289

157,038,002

159,455,103

161,871,411

164,287,044

166,704,687

169,121,766

171,538,507

173,953,453

176,368,856

178,784,747

181,199,797

183,616,094

186,032,643

188,447,228

190,862,368

193,277,613

195,693,825

198,109,015

200,524,477

202,939,323

205,355,672

207,771,197

210,186,316

212,602,940

215,018,872

217,433,686

219,850,418

222,266,315

224,680,750

227,095,084

229,512,704

231,928,518

234,344,371

236,759,404

239,175,318

241,590,277

244,006,839

246,423,282

248,840,359

251,254,880

253,670,404

256,084,270

258,498,530

260,914,435

263,328,945

265,745,475

268,160,697

270,575,863

272,991,794

275,405,890

277,820,730

280,236,256

282,651,618

285,066,604

287,481,429

289,896,907

292,311,641

294,727,521

297,143,533

299,557,657

301,974,027

304,389,137

306,805,299

309,221,256

311,637,141

314,052,527

316,468,413

318,884,030

321,299,093

323,715,600

326,131,076

328,547,998

330,963,887

333,379,370

335,795,486

338,210,775

340,626,948

343,043,659

345,459,815

347,875,673

350,292,487

352,708,290

355,125,177

357,540,909

359,956,876

362,372,813

364,788,891

367,204,161

369,619,640

372,035,743

374,450,389

376,866,208

379,281,305

381,697,126

384,113,355

386,529,610

388,944,754

391,360,944

393,776,305

396,192,233

398,607,648

401,023,403

403,439,651

405,856,956

408,272,435

410,688,792

413,104,065

415,517,439

417,933,403

420,349,873

422,765,244

425,181,055

427,599,027

430,016,536

432,433,414

434,849,911

437,267,293

439,682,132

442,097,346

444,512,168

446,927,453

449,343,164

449,343,164

454,174,655

456,588,593

459,004,983

461,419,218

463,835,090

466,250,388

468,667,675

471,085,391

473,503,339

475,919,151

478,335,425

480,750,860

483,166,859

485,581,911

487,996,904

490,413,021

492,829,843

495,245,922

497,662,056

500,077,852

502,495,484

504,913,664

507,329,950

509,745,400

512,162,233

514,577,796

516,992,665

519,408,582

521,825,691

524,242,175

526,658,409

529,075,350

531,491,865

533,907,350

536,322,341

538,737,263

541,153,446

543,569,184

545,986,095

548,402,519

550,818,415

553,233,019

555,650,203

558,065,511

560,480,471

562,896,706

565,311,914

In Work

2 .4158360000

2 .4151460000

2 .4153093333

2 .4155177500

2 .4157730000

2 .4158823333

2 .4159804286

2 .4159583750

2 .4160308889

2 .4159531000

2 .4158765455

2 .4159299167

2 .4160226923

2 .4160553571

2 .4160401333

2 .4159516875

2 .4159038235

2 .4159545556

2 .4158690526

2 .4158494000

2 .4158354762

2 .4158188636

2 .4159047391

2 .4159348333

2 .4159252000

2 .4160017692

2. 4159800741

2. 4160134643

2. 4161127586

2. 4160859667

2. 4161083226

2. 4160923438

2. 4160919394

2. 4160401176

2. 4160922000

2. 4161020556

2. 4161418108

2. 4161287895

2. 4161256154

2. 4161303250

2. 4161253902

2. 4161034762

2. 4161194884

2. 4161138636

2. 4160786444

2. 4160501739

2. 4160573404

2. 4160321458

2. 4160615510

2. 4160461000

2. 4160400784

2. 4160414231

2. 4160407547

2. 4159995370

2. 4160040545

2. 4159866429

2. 4160010526

2. 4160041724

2. 4160025932

2. 4159734333

2. 4159856066

2. 4159821774

2. 4159973810

2. 4159888906

2. 4159692615

2. 4159864091

2. 4159912090

2. 4159859412

2. 4160099565

2. 4160252286

2. 4160353099

2. 4160201806

2. 4160117260

2. 4160100946

2. 4159972933

2. 4160012368

2. 4160083506

2. 4159901026

2. 4159793418

2. 4159701625

2. 4159731481

2. 4159635976

2. 4159575542

2. 4159443214

2. 4159490824

2. 4159441512

2. 4159346667

2. 4159425000

2. 4159423820

2. 4159298444

2. 4159386593

2. 4159382065

2. 4159220430

2. 4159051489

2. 4159232000

2. 4159220625

2. 4159213505

2. 4159122857

2. 4159123030

2. 4159027700

2. 4159092970

2. 4159145294

2. 4159258155

2. 4159123077

2. 4159086095

2. 4158893396

2. 4158741121

2. 4158743981

2. 4158618807

2. 4158679545

2. 4158621351

2. 4158559196

2. 4158565841

2. 4158411404

2. 4158324348

2. 4158297931

2. 4158257949

2. 4158186780

2. 4158103277

2. 4158075583

2. 4157986860

2. 4157993525

2. 4158010813

2. 4157875565

2. 4157922160

2. 4157868016

2. 4157897559

2. 4157910625

2. 4157917907

2. 4157886692

2. 4157894122

2. 4157881061

2. 4157826541

2. 4157880597

2. 4157857481

2. 4157941029

2. 4157947956

2. 4157925362

2. 4157948633

2. 4157912500

2. 4157939574

2. 4158004155

2. 4158029021

2. 4158032847

2. 4158102552

2. 4158102055

2. 4158175306

2. 4158169527

2. 4158179597

2. 4158187533

2. 4158204702

2. 4158168487

2. 4158146405

2. 4158165130

2. 4158089613

2. 4158090256

2. 4158044904

2. 4158045949

2. 4158072642

2. 4158100625

2. 4158059255

2. 4158082963

2. 4158055521

2. 4158062988

2. 4158039273

2. 4158036325

2. 4158062934

2. 4158152143

2. 4158132249

2. 4158164235

2. 4158132456

2. 4157990640

2. 4158000173

2. 4158038678

2. 4158013943

2. 4158014489

2. 4158137119

2. 4158232360

2. 4158291285

2. 4158328389

2. 4158413978

2. 4158358901

2. 4158324918

2. 4158270000

2. 4158240703

2. 4158234624

2. 4158237594

2. 4158226330

2. 4158126614

2. 4158157000

2. 4158074241

2. 4158077604

2. 4158051192

2. 4158127577

2. 4158225179

2. 4158333622

2. 4158332538

2. 4158354798

2. 4158334673

2. 4158342950

2. 4158304030

2. 4158262574

2. 4158276897

2. 4158325637

2. 4158337659

2. 4158352233

2. 4158350338

2. 4158436731

2. 4158548517

2. 4158569048

2. 4158549763

2. 4158595896

2. 4158581972

2. 4158535748

2. 4158538698

2. 4158596806

2. 4158625576

2. 4158642615

2. 4158691781

2. 4158721136

2. 4158703620

2. 4158664009

2. 4158621659

2. 4158635982

2. 4158630400

2. 4158676770

2. 4158701278

2. 4158702412

2. 4158647118

2. 4158704478

2. 4158680130

2. 4158640991

2. 4158656910

2. 4158628803

In Work

1,207,921,500,000

4,830,299,000,000

10,868,902,500,000

19,324,156,000,000

30,197,180,000,000

43,485,903,000,000

59,191,545,000,000

77,310,696,000,000

97,849,282,500,000

120,797,690,000,000

146,160,569,500,000

173,946,996,000,000

204,153,963,000,000

236,773,474,000,000

271,804,567,500,000

309,241,872,000,000

349,098,162,000,000

391,384,701,000,000

436,064,430,500,000

483,169,950,000,000

532,691,796,000,000

584,628,242,000,000

639,006,884,000,000

695,789,316,000,000

754,976,712,500,000

816,608,689,000,000

880,624,831,500,000

947,077,376,000,000

1,015,975,516,500,000

1,087,238,790,000,000

1,160,940,157,500,000

1,237,039,392,000,000

1,315,562,176,500,000

1,396,471,307,000,000

1,479,856,595,000,000

1,565,634,258,000,000

1,653,849,199,000,000

1,744,445,119,000,000

1,837,463,667,000,000

1,932,904,400,000,000

2,030,753,534,000,000

2,131,003,413,000,000

2,233,702,617,500,000

2,338,798,374,000,000

2,446,279,785,000,000

2,556,181,245,000,000

2,668,535,497,000,000

2,783,269,200,000,000

2,900,482,063,500,000

3,020,057,800,000,000

3,142,060,300,500,000

3,266,488,186,000,000

3,393,329,425,500,000

3,522,527,514,000,000

3,654,206,325,000,000

3,788,267,252,000,000

3,924,793,909,500,000

4,063,719,221,000,000

4,205,052,720,000,000

4,348,752,390,000,000

4,494,941,434,500,000

4,643,517,962,000,000

4,794,547,023,000,000

4,947,945,472,000,000

5,103,735,292,500,000

5,262,018,630,000,000

5,422,692,503,000,000

5,585,759,734,000,000

5,751,311,943,000,000

5,919,262,055,000,000

6,089,617,247,000,000

6,262,324,560,000,000

6,437,463,499,500,000

6,615,035,898,000,000

6,794,992,650,000,000

6,977,411,838,000,000

7,162,257,025,000,000

7,349,442,165,000,000

7,539,063,812,500,000

7,731,104,800,000,000

7,925,600,196,000,000

8,122,469,902,000,000

8,321,766,086,000,000

8,523,451,860,000,000

8,727,616,357,500,000

8,934,161,772,000,000

9,143,105,050,500,000

9,354,529,668,000,000

9,568,340,115,500,000

9,784,516,185,000,000

10,003,194,337,500,000

10,224,250,812,000,000

10,447,655,200,500,000

10,673,469,277,000,000

10,901,853,772,500,000

11,132,569,200,000,000

11,365,702,333,000,000

11,601,211,139,000,000

11,839,178,587,500,000

12,079,514,200,000,000

12,322,345,723,000,000

12,567,587,739,000,000

12,815,278,849,000,000

13,065,254,124,000,000

13,317,696,577,500,000

13,572,466,681,000,000

13,829,671,729,500,000

14,089,379,868,000,000

14,351,427,884,000,000

14,616,001,510,000,000

14,882,919,072,000,000

15,152,248,720,000,000

15,424,036,756,500,000

15,698,136,129,000,000

15,974,692,377,500,000

16,253,703,254,000,000

16,535,120,062,500,000

16,818,930,049,000,000

17,105,145,442,000,000

17,393,814,840,000,000

17,684,854,704,000,000

17,978,379,208,000,000

18,274,327,710,000,000

18,572,575,168,000,000

18,873,377,125,000,000

19,176,516,072,000,000

19,482,136,931,000,000

19,790,160,832,000,000

20,100,596,046,000,000

20,413,414,710,000,000

20,728,681,510,000,000

21,046,346,442,000,000

21,366,390,150,000,000

21,688,945,669,000,000

22,013,848,102,500,000

22,341,264,340,000,000

22,671,026,739,000,000

23,003,177,013,000,000

23,337,786,763,500,000

23,674,754,740,000,000

24,014,200,327,500,000

24,356,100,286,000,000

24,700,377,273,000,000

25,047,048,960,000,000

25,396,205,815,000,000

25,747,705,681,000,000

26,101,701,024,000,000

26,458,027,784,000,000

26,816,787,783,500,000

27,177,961,500,000,000

27,541,561,799,000,000

27,907,516,768,000,000

28,275,902,995,500,000

28,646,752,750,000,000

29,019,905,690,000,000

29,395,564,770,000,000

29,773,582,992,000,000

30,154,073,507,000,000

30,537,012,279,000,000

30,922,369,360,000,000

31,310,053,260,500,000

31,700,237,031,000,000

32,092,769,428,000,000

32,487,763,680,000,000

32,885,131,537,500,000

33,284,943,030,000,000

33,687,211,443,000,000

34,091,984,892,000,000

34,499,021,349,000,000

34,908,547,915,000,000

35,320,398,156,000,000

35,734,500,356,000,000

36,151,239,965,000,000

36,570,439,560,000,000

36,991,959,462,500,000

37,415,933,456,000,000

37,842,514,509,000,000

38,271,472,327,000,000

38,702,791,179,500,000

39,136,492,620,000,000

39,572,690,650,000,000

40,011,074,649,000,000

40,451,907,799,500,000

40,895,120,100,000,000

41,340,790,050,000,000

41,788,914,903,000,000

42,239,471,175,000,000

42,692,418,228,000,000

43,147,622,700,000,000

43,605,474,050,000,000

44,065,535,987,500,000

44,528,169,312,000,000

44,993,163,117,500,000

45,460,765,154,000,000

45,930,826,305,000,000

46,403,327,908,000,000

46,878,037,063,000,000

47,355,207,768,000,000

47,834,711,266,500,000

48,316,686,600,000,000

48,800,982,759,000,000

49,287,688,011,000,000

49,776,922,342,000,000

50,268,644,700,000,000

50,762,707,722,500,000

51,259,192,489,000,000

51,758,058,406,500,000

52,259,531,064,000,000

52,763,478,619,500,000

53,269,645,485,000,000

53,778,140,438,500,000

54,289,197,440,000,000

54,802,536,019,500,000

55,318,215,904,000,000

55,836,423,317,500,000

56,357,175,384,000,000

56,880,276,747,000,000

57,405,767,344,000,000

57,933,751,591,500,000

58,464,105,920,000,000

58,996,762,948,500,000

59,531,780,628,000,000

60,069,205,605,000,000

60,609,186,736,000,000

61,151,533,987,500,000

61,696,429,526,000,000

62,243,686,701,000,000

62,793,300,108,000,000

63,345,181,477,000,000

63,899,774,150,000,000

64,456,567,329,000,000

65,015,735,448,000,000

65,577,467,064,500,000

66,141,494,757,000,000

In Work


NOTE: Berend Jan van der Zwaag of the Netherlands has brought to my attention that the palindromes checked for in the table below are possibly in error. His results differ from my own. I am looking into it, and will correct them as I find out who is correct. (Although I suspect that it's probably Berend who is correct....)

Below is a some data of the palindromes found within some files of very large numbers. Most of the data files are the results from this 196 quest, but in order to have a larger sample, I gathered some number files off of the web. I do not care if the calculations of the number files are accurate, (except for the 196 files I DO WANT THOSE TO BE ACCURATE!! :-) ) my goal was to just gather some very large number sets, and test them for palindromes.

Table Legend

The "Data Set Basis" is a general idea of what was being calculated to find the number. Most of them are my own 196 files.

"File Length" is the number of digits in the file claimed by the author. I didn't count the digits in other people's files, so I just have to trust that they were careful.

"File Location" is where I found the file from on the internet. Again, most of these are my own local files, but I provide a URL to the ones I can, from the internet, in case someone would like to verify my findings. (This would not hurt my feelings!!!)

"# of Even Pals" is how many palindromes of 6 digits long or greater that I found, which have an EVEN number of digits.

"# of Odd Pals" is how many palindromes of 7 digits long or greater that I found, which have an ODD number of digits.

"Percentage" is the percentage of even finds to odds.

Data Set Basis File Length File Location # of Even Pals # of Odd Pals Percentage
SQRT 2

SQRT 5

SQRT 6

SQRT 7

SQRT 8

SQRT 10

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

196 calc

2,000,000

1,000,000

1,000,000

1,000,000

1,000,000

1,000,000

1,000,000

2,000,000

3,000,000

4,000,000

5,000,000

6,000,000

7,000,000

8,000,000

9,000,000

10,000,000

11,000,000

12,000,000

13,000,000

14,000,000

15,000,000

16,000,000

17,000,000

18,000,000

19,000,000

20,000,000

21,000,000

22,000,000

23,000,000

24,000,000

25,000,000

26,000,000

27,000,000

28,000,000

29,000,000

30,000,000

31,000,000

32,000,000

33,000,000

34,000,000

35,000,000

36,000,000

37,000,000

38,000,000

39,000,000

40,000,000

Robert Nemiroff and Jerry Bonnell

Robert Nemiroff and Jerry Bonnell

Robert Nemiroff and Jerry Bonnell

Robert Nemiroff and Jerry Bonnell

Robert Nemiroff and Jerry Bonnell

Robert Nemiroff and Jerry Bonnell

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local file

Local File

Local file

Local file

Local file

948

655

625

628

591

646

722

1,033

1,229

1,304

1,559

1,583

1,532

1,669

1,659

2,435

2,134

2,061

4,641

2,098

2,290

2,624

2,660

2,426

2,700

3,036

2,997

3,111

3,219

2,713

5,161

7,266

2,999

3,608

3,773

3,406

3,925

4,054

3,815

4,391

3,548

4,074

3,848

3,814

4,231

4,699

1,649

906

918

905

872

868

887

1,754

2,401

3,154

3,687

4,334

4,645

5,320

5,643

6,164

6,434

6,928

6,925

7,317

7,925

7,758

8,041

8,702

8,910

9,036

8,945

9,324

9,404

10,028

10,249

9,978

10,631

10,264

10,438

10,550

10,676

10,782

11,218

11,336

11,607

11,650

11,739

11,930

12,005

11,870

57

72

68

69

67

74

81

59

51

41

42

37

33

31

29

40

33

30

67

29

29

34

33

28

30

34

34

33

34

27

50

73

28

35

36

32

37

38

34

39

31

35

33

32

35

40

I find this very interesting!! There are the same number of even digit palindromes as odd ones, from here to infinity. Yet, in every single test case above, there are about 3 times as many odd digit palindromes as evens. Even though I am technically starting with a harder search, because there are more digits. (This holds true for the other data sets that I don't have listed above, as well...)

If I had to guess the reason for this, I would say that it has to do with the probability of the double digit in the middle of the evens.

Richard Farmbrough from the United Kingdom sent me the following:

I am interested in your observations on even/odd pal distributions.

Your suggested reason (double digit) is not valid because XX has the same probability as XYX (where Y can be = or <> X).

In both cases this is 10%.

Rgds,
Richard.

I've never seen anyone discussing this on any of the pages that I have read. Does anyone have any input??