A031903 Lucky numbers with size of gaps equal to 20 (upper terms).

957, 1797, 2943, 3003, 3027, 3153, 3747, 4227, 4695, 4761, 5211, 5547, 5637, 6621, 7629, 7737, 8253, 8535, 9915, 9957, 10173, 10311, 10341, 11157, 12357, 12519, 12699, 13677, 13893, 14775, 14817, 14997, 15291, 15333, 15417, 15567

Offset: 1

Author

Patrick De Geest

Keywords

• nonn

Links

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

Crossrefs

Cf. A000959, A031902.

Programs

Mathematica

t = Range[1, 20000, 2]; sieve[n_] := Module[{k = t[[n]]},  t = Delete[t, Table[{i}, {i, k, Length[t], k}]]]; n = 1; While[ t[[n]] < Length[t], n++; sieve[n]]; Transpose[Select[Partition[t,2,1], Last[#]- First[#]==20&]][[2]]  (* Harvey P. Dale, Apr 07 2011 *)