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A298019
Partial sums of A298016.
1
1, 7, 19, 31, 55, 91, 115, 157, 217, 253, 313, 397, 445, 523, 631, 691, 787, 919, 991, 1105, 1261, 1345, 1477, 1657, 1753, 1903, 2107, 2215, 2383, 2611, 2731, 2917, 3169, 3301, 3505, 3781, 3925, 4147, 4447, 4603, 4843, 5167, 5335, 5593, 5941, 6121, 6397, 6769, 6961, 7255, 7651, 7855, 8167, 8587
OFFSET
0,2
FORMULA
From Colin Barker, Jan 16 2018: (Start)
G.f.: (1 + 6*x + 12*x^2 + 10*x^3 + 12*x^4 + 12*x^5 + x^6) / ((1 - x)^3*(1 + x + x^2)^2).
a(n) = a(n-1) + 2*a(n-3) - 2*a(n-4) - a(n-6) + a(n-7) for n>6.
(End)
PROG
(PARI) Vec((1 + 6*x + 12*x^2 + 10*x^3 + 12*x^4 + 12*x^5 + x^6) / ((1 - x)^3*(1 + x + x^2)^2) + O(x^80)) \\ Colin Barker, Jan 16 2018
CROSSREFS
Cf. A298016.
Sequence in context: A216530 A114564 A191118 * A169605 A216532 A249375
KEYWORD
nonn,easy
AUTHOR
Chaim Goodman-Strauss and N. J. A. Sloane, Jan 13 2018
STATUS
approved