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%I #9 Jul 21 2017 05:32:21
%S 1,3,4,5,6,8,9,10,13,14,17,18,19,26,33,38,46,62,82
%N Positive numbers that are not the sum of two nonprime squarefree numbers (A000469).
%C The sequence is conjectured to be complete.
%t nmax = 82; f[x_] := Sum[Boole[SquareFreeQ[k] && PrimeNu[k] != 1] x^k, {k, 1, nmax}]^2; b = Exponent[#, x] & /@ List @@ Normal[Series[f[x], {x, 0, nmax}]]; c = Complement[Range[nmax], b][[1 ;; 19]]
%Y Cf. A000469, A014092, A071068, A071331, A098235, A239508, A239509.
%K nonn,more
%O 1,2
%A _Ilya Gutkovskiy_, Jul 20 2017
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