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 A060421 Numbers n such that the first n digits of the decimal expansion of Pi form a prime. 13
 1, 2, 6, 38, 16208, 47577, 78073, 613373 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The Brown link states that in 2001 Ed T. Prothro reported discovering that 16208 gives a probable prime and that Prothro verified that all values for 500 through 16207 digits of Pi are composites. - Rick L. Shepherd, Sep 10 2002 The corresponding primes are in A005042. - Alexander R. Povolotsky, Dec 17 2007 LINKS K. S. Brown, Primes in the Decimal Expansion of Pi [Broken link?] K. S. Brown, Primes in the Decimal Expansion of Pi [Cached copy] Prime Curios, 314159 Prime Curios, 31415...36307 (16208-digits) Eric Weisstein's World of Mathematics, Constant Primes Eric Weisstein's World of Mathematics, Integer Sequence Primes Eric Weisstein's World of Mathematics, Pi Digits Eric Weisstein's World of Mathematics, Pi-Prime EXAMPLE 3 is prime, so a(1) = 1; 31 is prime, so a(2) = 2; 314159 is prime, so a(3) = 6; ... MATHEMATICA Do[If[PrimeQ[FromDigits[RealDigits[N[Pi, n + 10], 10, n][]]], Print[n]], {n, 1, 9016} ] CROSSREFS Cf. A005042, A007523, A047658. Primes in other constants: A064118 (e), A065815 (gamma), A064119 (phi), A118328 (Catalan's constant), A115377 (sqrt(2)), A119344 (sqrt(3)), A228226 (log 2), A228240 (log 10), A119334 (zeta(3)), A122422 (Soldner's constant), A118420 (Glaisher-Kinkelin constant), A174974 (Golomb-Dickman constant), A118327 (Khinchin's constant). Sequence in context: A005530 A072191 A118324 * A054970 A211348 A295912 Adjacent sequences:  A060418 A060419 A060420 * A060422 A060423 A060424 KEYWORD hard,nonn,base AUTHOR Michel ten Voorde, Apr 05 2001 EXTENSIONS a(6) = 47577 from Eric W. Weisstein, Apr 01 2006 a(7) = 78073 from Eric W. Weisstein, Jul 13 2006 a(8) = 613373 from Adrian Bondrescu, May 29 2016 STATUS approved

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Last modified March 31 03:48 EDT 2020. Contains 333136 sequences. (Running on oeis4.)