A271233 Composite integers sandwiched between primes p, q with q-p = 8.
90, 91, 92, 93, 94, 95, 96, 360, 361, 362, 363, 364, 365, 366, 390, 391, 392, 393, 394, 395, 396, 402, 403, 404, 405, 406, 407, 408, 450, 451, 452, 453, 454, 455, 456, 480, 481, 482, 483, 484, 485, 486, 492, 493, 494, 495, 496, 497, 498, 684, 685, 686, 687, 688, 689, 690
Offset: 1
Keywords
Examples
The composite number 90 is sandwiched between consecutive primes 89 and 97, and 97-89=8, so 90 is a member of the sequence.
Links
- Laurent Coppey, Décompositions multiplicatives directes des entiers, Diagrammes, 65-66 (2011), p. 1-68, in French, see J8 p. 11.
Programs
-
Mathematica
Range[#[[1]]+1,#[[2]]-1]&/@Select[Partition[Prime[Range[150]],2,1],#[[2]]-#[[1]] == 8&]//Flatten (* Harvey P. Dale, May 15 2022 *)
-
PARI
lista(nn) = {forcomposite(c=4, nn, if ((p=precprime(c)) && ((nextprime(c)-p)==8), print1(c, ", ")););}