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A075495
Convolution of A075298 with A056594.
1
1, 1, -6, 4, 7, -15, 8, 12, -31, 29, 10, -72, 95, -11, -160, 264, -111, -311, 682, -484, -505, 1673, -1656, -524, 3857, -4987, 602, 8240, -13825, 6189, 15872, -35888, 26209, 25553, -87654, 88308, 24903, -200863, 264264, -38500, -426623, 729389, -341270, -814744, 1885407, -1411931, -1288224
OFFSET
0,3
FORMULA
a(n) = -a(n-1) - 2a(n-2) - a(n-4) + a(n-5); a(0)=1, a(1)=1, a(2)=-6, a(3)=4, a(4)=7.
G.f.: (1 + 2x - 3x^2)/(1 + x + 2x^2 + x^4 - x^5).
MATHEMATICA
CoefficientList[Series[(1 + 2x - 3x^2)/(1 + x + 2x^2 + x^4 - x^5), {x, 0, 50}], x]
CROSSREFS
KEYWORD
easy,sign
AUTHOR
Mario Catalani (mario.catalani(AT)unito.it), Sep 19 2002
STATUS
approved