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A078068
Expansion of (1-x)/(1+2*x+2*x^2-x^3).
0
1, -3, 4, -1, -9, 24, -31, 5, 76, -193, 239, -16, -639, 1549, -1836, -65, 5351, -12408, 14049, 2069, -44644, 99199, -107041, -28960, 371201, -791523, 811684, 330879, -3076649, 6303224, -6122271, -3438555, 25424876, -50094913, 45901519, 33811664, -209521279, 397320749, -341787276
OFFSET
0,2
FORMULA
a(0) = 1, a(1) = -3, a(2) = 4, a(n) = -2*a(n-1) - 2*a(n-2) + a(n-3) for n > 2. - Jinyuan Wang, Apr 07 2020
PROG
(PARI) Vec((1-x)/(1+2*x+2*x^2-x^3) + O(x^50)) \\ Jinyuan Wang, Apr 07 2020
CROSSREFS
Sequence in context: A136158 A164948 A102051 * A054649 A138263 A147721
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Nov 17 2002
STATUS
approved