1,1

a(3)=a(4)=6 as 7+6=13, 11+6=17, 13+6=19 and 17+6=23 are all prime.

Cf. A087551.

Adjacent sequences: A087570 A087571 A087572 this_sequence A087574 A087575 A087576

Sequence in context: A141328 A031131 A035551 this_sequence A018937 A103413 A103412

nonn,fini,full

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Sep 17 2003

Edited by Don Reble (djr(AT)nk.ca), Sep 23, 2003