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 A046107 Triangle of prime numbers in which n-th row lists all primes p such that 1/p has decimal period n, n >= 1. 15
 3, 11, 37, 101, 41, 271, 7, 13, 239, 4649, 73, 137, 333667, 9091, 21649, 513239, 9901, 53, 79, 265371653, 909091, 31, 2906161, 17, 5882353, 2071723, 5363222357, 19, 52579, 1111111111111111111, 3541, 27961, 43, 1933, 10838689, 23, 4093 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The number of numbers in each row n is given by A112505(n). In the 18th century, the Japanese mathematician Ajima Naonobu (aka Ajima Chokuyen) gave the terms through 5882353 (Smith and Mikami, p. 199). - Jonathan Sondow, May 25 2013 REFERENCES Ajima Naonobu (aka Ajima Chokuyen), Fujin Isshũ (Periods of Decimal Fractions). LINKS Rows n=1..352, flattened David Eugene Smith and Yoshio Mikami, A History of Japanese Mathematics, Open Court, Chicago, 1914; chapter X. Eric Weisstein's World of Mathematics, Decimal Expansion. Index entries for sequences related to decimal expansion of 1/n EXAMPLE First rows of irregular triangle are: 3; 11; 37; 101; 41, 271; 7, 13; 239, 4649; 73, 137; 333667; 9091; 21649, 513239; 9901; 53, 79, 265371653; 909091; 31, 2906161; 17, 5882353; ... MATHEMATICA pp={}; Do[f=Transpose[FactorInteger[10^n-1]][[1]]; p=Complement[f, pp]; pp=Union[pp, p]; Print[p], {n, 66}] (* T. D. Noe, Sep 08 2005 *) CROSSREFS Cf. A007138 (first column). Sequence in context: A095088 A306362 A007138 * A243110 A061075 A005422 Adjacent sequences: A046104 A046105 A046106 * A046108 A046109 A046110 KEYWORD nonn,tabf,base AUTHOR Eric W. Weisstein EXTENSIONS First 276 rows in b-file from T. D. Noe, Jun 01 2010 Rows n=277..322 in b-file from Ray Chandler, May 01 2017 Rows n=323..352 in b-file from Max Alekseyev, Apr 26 2022 STATUS approved

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Last modified March 5 06:19 EST 2024. Contains 370537 sequences. (Running on oeis4.)