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A375284
Expansion of (1 - x - x^5)/((1 - x - x^5)^2 - 4*x^6).
1
1, 1, 1, 1, 1, 2, 7, 16, 29, 46, 68, 107, 191, 364, 686, 1234, 2125, 3596, 6148, 10754, 19132, 34121, 60361, 105725, 184207, 321227, 562628, 989397, 1742190, 3064093, 5377732, 9424960, 16515877, 28964243, 50840968, 89280116, 156762020, 275136201, 482728432
OFFSET
0,6
FORMULA
a(n) = 2*a(n-1) - a(n-2) + 2*a(n-5) + 2*a(n-6) - a(n-10).
a(n) = Sum_{k=0..floor(n/5)} binomial(2*n-8*k,2*k).
PROG
(PARI) my(N=40, x='x+O('x^N)); Vec((1-x-x^5)/((1-x-x^5)^2-4*x^6))
(PARI) a(n) = sum(k=0, n\5, binomial(2*n-8*k, 2*k));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 09 2024
STATUS
approved