A152023 Numbers in A152022 which are not products of terms of A152021.

65, 260, 273, 325, 1025, 1029, 1040, 1045, 1092, 1105, 1281, 1300, 1345, 1365, 4097, 4100, 4116, 4160, 4165, 4180, 4368, 4420, 4433, 5124, 5125, 5185, 5200, 5380, 5460, 16385, 16388, 16400, 16401, 16405, 16464, 16465, 16640, 16645, 16660, 16705, 16709, 16720

Offset: 1

Author

Vladimir Shevelev, Nov 20 2008, Jun 11 2009

Keywords

• nonn

Crossrefs

Cf. A000695, A152021, A152022.

Programs

Mathematica

f[n_] := FromDigits[IntegerDigits[n, 2], 4];  s = Array[f, 300, 2]; div[a_, b_] := Divisible[a, b] && a > b; n = 1; s0 = s; While[Length[s] > n, s = Select[s, ! div[#, s[[n]]] &]; n++]; s1 = Complement[s0, s]; aQ[n_, s_] := Times @@ (s^(IntegerExponent[n, #] & /@ s)) == n; Select[s1, ! aQ[#, s] &] (* Amiram Eldar, Aug 31 2019 *)

Extensions

a(12)-a(14) inserted and more terms added by Amiram Eldar, Aug 31 2019