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A290136
Positive numbers that are not the sum of two nonprime squarefree numbers (A000469).
1
1, 3, 4, 5, 6, 8, 9, 10, 13, 14, 17, 18, 19, 26, 33, 38, 46, 62, 82
OFFSET
1,2
COMMENTS
The sequence is conjectured to be complete.
MATHEMATICA
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]]
KEYWORD
nonn,more
AUTHOR
Ilya Gutkovskiy, Jul 20 2017
STATUS
approved