A026452 a(n) = least positive integer > a(n-1) and not a(i)*a(j)+2 for i<=1<=j<=n.

3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 15, 16, 19, 21, 24, 25, 28, 31, 33, 35, 36, 39, 40, 43, 45, 46, 48, 49, 53, 55, 57, 60, 61, 63, 64, 68, 69, 70, 71, 73, 75, 76, 79, 81, 84, 85, 87, 88, 89, 90, 91, 94, 96, 99, 100, 103, 104, 105, 108, 109

Offset

1,1

Links

Ivan Neretin, Table of n, a(n) for n = 1..1000

Mathematica

a = {3, 4}; used = {a[[1]]^2 + 2, a[[1]]*a[[2]] + 2, a[[2]]^2 + 2}; Do[k = a[[-1]] + 1; While[MemberQ[used, k], k++]; AppendTo[a, k]; used = Union[used, k*a + 2], {n, 3, 60}]; a (* Ivan Neretin, Mar 06 2016 *)

Crossrefs

Cf. A026443 and references therein.

Sequence in context: A299532 A026432 A026436 * A271928 A039157 A234321

Adjacent sequences: A026449 A026450 A026451 * A026453 A026454 A026455

Keyword

nonn

Author

Clark Kimberling

Status

approved