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A298785
Partial sums of A298784.
2
1, 5, 11, 21, 35, 51, 71, 95, 121, 151, 185, 221, 261, 305, 351, 401, 455, 511, 571, 635, 701, 771, 845, 921, 1001, 1085, 1171, 1261, 1355, 1451, 1551, 1655, 1761, 1871, 1985, 2101, 2221, 2345, 2471, 2601, 2735, 2871, 3011, 3155, 3301, 3451, 3605, 3761, 3921, 4085, 4251, 4421, 4595, 4771
OFFSET
0,2
FORMULA
G.f.: (1 + x^2)*(1 + 3*x + x^2) / ((1 - x)^2*(1 - x^3)).
a(n) = 2*a(n-1) - a(n-2) + a(n-3) - 2*a(n-4) + a(n-5) for n>4. - Colin Barker, Jan 27 2018
PROG
(PARI) Vec((1 + x^2)*(1 + 3*x + x^2) / ((1 - x)^3*(1 + x + x^2)) + O(x^60)) \\ Colin Barker, Jan 27 2018
CROSSREFS
Cf. A298784.
Sequence in context: A372906 A166480 A164096 * A163787 A166863 A163704
KEYWORD
nonn,easy
AUTHOR
N. J. A. Sloane, Jan 26 2018
STATUS
approved