A155767 Least prime p such that p - 2n is prime, but not both p-2k and p-2(n-k) are prime for 0 < k < n.

2, 5, 11, 11, 31, 29, 31, 61, 59, 31, 127, 233, 61, 127, 101, 61, 223, 233, 139, 277, 311, 149, 613, 359, 227, 331, 449, 163, 547, 521, 251, 919, 983, 179, 571, 353, 563, 1693, 599, 277, 739, 773, 307, 907, 1409, 331, 1399, 1721, 389, 1471, 1721, 853, 2503, 929

Offset: 0

Author

T. D. Noe, Jan 27 2009

Keywords

• nonn

Comments

Does a(n) exist for all n? It appears that a(3n) is less than a(3n-1) and a(3n+1) for all n except 1, 2 and 12.

Links

• T. D. Noe, Table of n, a(n) for n = 0..2000

Formula

a(n) = A103147(n) + n = A155766(n) + 2n.