A375198 Numbers k such that A025487(k)-1 and A025487(k)+1 are twin primes.

3, 4, 6, 9, 13, 15, 20, 21, 24, 29, 30, 42, 54, 56, 59, 72, 77, 83, 96, 104, 105, 109, 138, 161, 166, 174, 186, 203, 208, 221, 232, 237, 266, 270, 288, 295, 336, 338, 347, 387, 389, 395, 400, 401, 449, 468, 469, 472, 479, 506, 520, 543, 584, 617, 633, 643, 668

Offset: 1

Author

Amiram Eldar, Aug 04 2024

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A001097, A001359, A006512, A014574, A025487, A375197.

Similar sequences: A321995, A353302.

Programs

Mathematica

Position[Cases[Import["https://oeis.org/A025487/b025487.txt", "Table"], {, }][[;; , 2]], _?(PrimeQ[# - 1] && PrimeQ[# + 1] &)] // Flatten

Formula

A025487(a(n)) = A375197(n).