A192585 Monotonic ordering of set S generated by these rules: if x and y are in S and xy+1 is a prime, then xy+1 is in S, and 2, 5, 8, 11, and 14 are in S.

2, 5, 8, 11, 14, 17, 23, 29, 41, 47, 59, 71, 83, 89, 113, 137, 167, 179, 197, 227, 233, 239, 359, 467, 479, 569, 659, 719, 827, 1097, 1163, 1319, 1433, 1439, 1583, 1913, 2339, 2879, 3167, 3347, 3833, 4679, 5273, 9227, 10067, 11579, 15359, 18713, 20063

Offset

1,1

Comments

Last term is a(70) = 15785183. - Giovanni Resta, Mar 21 2013

Links

Giovanni Resta, Table of n, a(n) for n = 1..70 (full sequence)

Mathematica

start = {2, 5, 8, 11, 14}; seq = {}; new = start; While[new != {}, seq = Union[seq, new]; fresh = new; new = {}; Do[If[PrimeQ[u = x*y + 1], If[! MemberQ[seq, u], AppendTo[new, u]]], {x, seq}, {y, fresh}]]; seq (* Giovanni Resta, Mar 21 2013 *)

Crossrefs

Cf. A192476, A192580, A192584.

Sequence in context: A190006 A135677 A355135 * A344162 A163516 A000093

Adjacent sequences: A192582 A192583 A192584 * A192586 A192587 A192588

Keyword

nonn,fini,full

Author

Clark Kimberling, Jul 05 2011

Status

approved