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A107849
Expansion of (1 + x)^2 / ((1 - x^2 - 2*x^3)*(1 + x^4)).
6
1, 2, 2, 4, 5, 6, 12, 16, 25, 42, 58, 92, 141, 206, 324, 488, 737, 1138, 1714, 2612, 3989, 6038, 9212, 14016, 21289, 32442, 49322, 75020, 114205, 173662, 264244, 402072, 611569, 930562, 1415714, 2153700, 3276837, 4985126, 7584236, 11538800
OFFSET
0,2
FORMULA
a(n) = A052947(n+2) + A014017(n+6). - Ralf Stephan, Nov 30 2010
a(n) = a(n-2) + 2*a(n-3) - a(n-4) + a(n-6) + 2*a(n-7) for n>6. - Colin Barker, Apr 30 2019
MATHEMATICA
CoefficientList[Series[(1 + x)^2 / ((1 - x^2 - 2*x^3)*(1 + x^4)), {x, 0, 39}], x] (* James C. McMahon, Feb 19 2024 *)
PROG
(PARI) Vec((1 + x)^2 / ((1 - x^2 - 2*x^3)*(1 + x^4)) + O(x^45)) \\ Colin Barker, Apr 30 2019
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Creighton Dement, May 25 2005
STATUS
approved