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Coefficients in the series (1 + x - 4x^4 - 6x^6 - 8x^8 - 9x^9 - 10x^10 - 12x^12 - 14x^14 - ... )/(1 - 2x^2 - 3x^3 - 5x^5 - 7x^7 - 11x^11 - 13x^13 - ... ).
0

%I #2 Mar 30 2012 17:30:28

%S 1,1,2,5,3,21,20,68,127,216,588,945,2310,4464,9065,19731,38039,82599,

%T 165226,342520,711496,1442555,3015297,6145475,12711995,26183208,

%U 53750956,111108083,228062512,470499012,968320551,1993099704

%N Coefficients in the series (1 + x - 4x^4 - 6x^6 - 8x^8 - 9x^9 - 10x^10 - 12x^12 - 14x^14 - ... )/(1 - 2x^2 - 3x^3 - 5x^5 - 7x^7 - 11x^11 - 13x^13 - ... ).

%t CoefficientList[ Series[ (1 + x - Apply[ Plus, Select[ Range[ 2, 50 ], !PrimeQ[ # ] & ]*x^Select[ Range[ 2, 50 ], !PrimeQ[ # ] & ] ] ) / (1 - Apply[ Plus, Select[ Range[ 2, 50 ], PrimeQ[ # ] & ]*x^Select[ Range[ 2, 50 ], PrimeQ[ # ] & ] ] ), {x, 0, 50} ], x ]

%K nonn

%O 0,3

%A _Robert G. Wilson v_, Dec 16 2000