A282428 Numbers k such that A264097(k) = A264098(k), so : A264097(k)*2^k-1 and A264098(k)*2^k+1 are twin primes.

1, 2, 6, 10, 18, 29, 63, 155, 211, 264, 546, 1032, 1156, 1321, 1553, 3460, 4901, 5907, 8335, 8529, 11455, 13153

Offset

1,2

Comments

a(23) is > 31000.

The A264097(k) are : 3, 3, 3, 15, 3, 45, 9, 105, 9, 165, 297, 177, 1035, 1065, 291, 2403, 2565, 5775, 3975, 459, 915, 3981

Links

Table of n, a(n) for n=1..22.

Mathematica

With[{nn = 600}, Flatten@ Position[Transpose@ {Table[k = 3; While[! PrimeQ[k 2^n - 1], k += 6]; k, {n, nn}], Table[k = 3; While[! PrimeQ[k 2^n + 1], k += 6]; k, {n, nn}]}, w_ /; SameQ @@ w]] (* Michael De Vlieger, Feb 16 2017 *)

Crossrefs

Cf. A264097, A264098.

Sequence in context: A320678 A050844 A328960 * A174316 A095357 A095358

Adjacent sequences: A282425 A282426 A282427 * A282429 A282430 A282431

Keyword

nonn,more

Author

Pierre CAMI, Feb 15 2017

Status

approved