A305632 Expansion of Product_{r = 1 or not a perfect power} 1/(1 + (-x)^r).
1, 1, 0, 1, 2, 2, 1, 2, 4, 3, 2, 4, 6, 5, 4, 7, 10, 8, 7, 11, 15, 13, 12, 17, 22, 19, 18, 25, 30, 28, 26, 35, 42, 39, 38, 49, 59, 56, 54, 69, 81, 77, 76, 94, 110, 105, 105, 127, 147, 141, 142, 171, 195, 189, 190, 227, 257, 250, 254, 299, 335, 328, 334, 390, 432
Offset: 0
Keywords
Examples
O.g.f.: 1/((1 - x)(1 + x^2)(1 - x^3)(1 - x^5)(1 + x^6)(1 - x^7)(1 + x^10)...).
Crossrefs
Programs
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Mathematica
nn=20; radQ[n_]:=Or[n==1,GCD@@FactorInteger[n][[All,2]]==1]; ser=Product[1/(1+(-x)^p),{p,Select[Range[nn],radQ]}]; Table[SeriesCoefficient[ser,{x,0,n}],{n,0,nn}]