A074069 Numbers k such that S(k) = Sum_{i=1..k} A068119(i) = 3*k.

1, 2, 10, 18, 20, 25, 26, 43, 46, 55, 56, 71, 79, 104, 107, 111, 112, 113, 123, 133, 136, 140, 142, 144, 145, 147, 150, 155, 165, 195, 196, 200, 204, 206, 210, 214, 216, 253, 254, 259, 260, 264, 267, 327, 335, 343, 360, 363, 375, 376, 380, 387, 388, 393

Offset: 1

Author

Benoit Cloitre, Aug 30 2002

Keywords

• nonn

Programs

Mathematica

ce[n_] := Length[NestWhileList[#*Ceiling[#] &, n + 1/4, ! IntegerQ[#] &]] - 1; nn = Range[395]; t = Accumulate[ce /@ nn]; Select[nn, t[[#]] == 3*# &] (* Jayanta Basu, Jul 29 2013 *)

Extensions

Name clarified by Sean A. Irvine, Jan 08 2025