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 A099229 Numbers n such that n*((2^61-1)^2) - 1 and n*((2^61-1)^2) + 1 are twin primes. 2
 4020, 5100, 6702, 7350, 9810, 17022, 18540, 19050, 29832, 33402, 37488, 54852, 65292, 67518, 90198, 99162, 103890, 115098, 124458, 135282, 136692, 146982, 152610, 156258, 161892, 164700, 180318, 187038, 191382, 204330, 205170, 220020, 221280, 225528, 226230, 231390, 231858 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..37. MATHEMATICA With[{c=(2^61-1)^2}, Select[Range[232000], AllTrue[c #+{1, -1}, PrimeQ]&]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 17 2021 *) PROG (PARI) isok(n) = my(p); ispseudoprime(p=n*((2^61-1)^2) - 1) && ispseudoprime(p+2); \\ Michel Marcus, Sep 23 2019 CROSSREFS Cf. A099230 A099231. Sequence in context: A107285 A252349 A282128 * A205889 A236521 A235658 Adjacent sequences: A099226 A099227 A099228 * A099230 A099231 A099232 KEYWORD nonn AUTHOR Pierre CAMI, Oct 07 2004 EXTENSIONS More terms from Michel Marcus, Sep 23 2019 STATUS approved

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Last modified December 4 07:54 EST 2023. Contains 367557 sequences. (Running on oeis4.)