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A152023
Numbers in A152022 which are not products of terms of A152021.
5
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
1,1
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 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Nov 20 2008, Jun 11 2009
EXTENSIONS
a(12)-a(14) inserted and more terms added by Amiram Eldar, Aug 31 2019
STATUS
approved