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 A065987 Numbers n such that the first n binary digits of Pi expressed in decimal forms a prime. 4
 2, 23, 31, 35, 124, 323, 2787, 5717, 6506, 8980, 106817 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE The first 23 binary digits of Pi (A004601) are 11001001000011111101101 = 6588397 in decimal, which is a prime. MATHEMATICA Do[ If[ PrimeQ[ FromDigits[ First[ RealDigits[Pi, 2, n]], 2]], Print[n]], {n, 1, 7000} ] CROSSREFS Cf. A004601, A117721 (the primes themselves). Sequence in context: A090150 A106102 A053232 * A107153 A049544 A049568 Adjacent sequences:  A065984 A065985 A065986 * A065988 A065989 A065990 KEYWORD base,nonn AUTHOR Robert G. Wilson v, Dec 10 2001 EXTENSIONS 8980 from Hans Havermann, Jul 23 2006 106817 from Hans Havermann, Sep 06 2006 STATUS approved

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Last modified December 13 06:15 EST 2018. Contains 318082 sequences. (Running on oeis4.)