A134305 Numbers k such that A134303(k) is the lesser of twin primes, A134303(k) = A134304(k).

1, 2, 3, 4, 40, 59, 60, 61, 62, 241, 276, 404, 2159, 2160, 2161

Offset

1,2

Links

Table of n, a(n) for n=1..15.

Prog

(PARI) a3(n) = {my(k=1); while (!(isprime(k*2^n*(k*2^n-1)-1)), k++); k; }
a4(n) = {my(k=1); while (!(isprime(p=k*2^n*(k*2^n-1)-1) && isprime(p+2)), k++); k; }
isok(n) = a3(n) == a4(n); \\ Michel Marcus, Sep 17 2019

Crossrefs

Cf. A134303, A134304.

Sequence in context: A302943 A037326 A024634 * A000033 A270350 A060411

Adjacent sequences: A134302 A134303 A134304 * A134306 A134307 A134308

Keyword

nonn,more

Author

Pierre CAMI, Oct 19 2007

Extensions

a(12)-a(15) from Jinyuan Wang, Mar 05 2020

Status

approved