A126233 Smallest number k such that (prime(k+1)+prime(k))/2 is odd and divisible by n-th odd prime.

4, 6, 8, 25, 12, 88, 78, 19, 121, 24, 29, 46, 31, 126, 186, 153, 156, 379, 197, 139, 280, 132, 285, 380, 155, 63, 334, 1005, 203, 75, 77, 516, 314, 445, 87, 1075, 93, 95, 1872, 254, 697, 1201, 270, 425, 429, 447, 304, 2187, 124, 488, 1153, 128, 335, 136, 547, 742

Offset

1,1

Links

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

Mathematica

f[n_] := Block[{k = 1, c}, While[c = (Prime[k + 1] + Prime[k])/2; Mod[c, 2] == 0 || Mod[c, Prime[n + 1]] > 0, k++ ]; k]; Table[f[n], {n, 56}] (* Ray Chandler, Jan 09 2007 *)

Crossrefs

Cf. A072569, A072572, A072573, A126228, A126229, A126230, A124619, A124620, A126231, A124622.

Sequence in context: A361662 A106366 A019160 * A059889 A058011 A278374

Adjacent sequences: A126230 A126231 A126232 * A126234 A126235 A126236

Keyword

nonn

Author

Artur Jasinski, Dec 21 2006

Extensions

Edited and extended by Ray Chandler, Jan 09 2007

Status

approved