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A262593
Expansion of (1-3*x)^3/((1-x)^4*(1-4*x)).
2
1, -1, -3, -1, 13, 63, 237, 879, 3357, 13135, 52061, 207519, 829037, 3314719, 13256973, 53025423, 212098557, 848390319, 3393556477, 13574220095, 54296873421, 217187485439, 868749932077, 3474999717039, 13899998855133, 55599995405583, 222399981605277, 889599926401759, 3558399705585197
OFFSET
0,3
COMMENTS
Suggested by A262592.
FORMULA
a(n + 1) = (1/3)*(12*a(n) - 4*n^3 + 18*n^2 + 4*n - 15), a(0) = 1. - Ilya Gutkovskiy, Oct 22 2015
From Colin Barker, Oct 23 2015: (Start)
a(n) = 8*a(n-1)-22*a(n-2)+28*a(n-3)-17*a(n-4)+4*a(n-5) for n>4.
a(n) = (77+4^(1+n)-84*n-126*n^2+36*n^3)/81.
(End)
PROG
(PARI) Vec((1-3*x)^3/((1-x)^4*(1-4*x)) + O(x^40)) \\ Michel Marcus, Oct 23 2015
(PARI) a(n) = (77+4^(1+n)-84*n-126*n^2+36*n^3)/81 \\ Colin Barker, Oct 23 2015
CROSSREFS
Cf. A262592.
Sequence in context: A008826 A103440 A116483 * A010290 A074960 A287740
KEYWORD
sign,easy
AUTHOR
N. J. A. Sloane, Oct 22 2015
STATUS
approved