A099229 Numbers k such that k*((2^61-1)^2) - 1 and k*((2^61-1)^2) + 1 are twin primes.

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

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