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A213824
Antidiagonal sums of the convolution array A213822.
3
4, 30, 114, 310, 690, 1344, 2380, 3924, 6120, 9130, 13134, 18330, 24934, 33180, 43320, 55624, 70380, 87894, 108490, 132510, 160314, 192280, 228804, 270300, 317200, 369954, 429030, 494914, 568110, 649140
OFFSET
1,1
COMMENTS
Every term is even.
FORMULA
a(n) = (2*n + 5*n^2 + 6*n^3 + 3*n^4)/4 = n*(1 + n)*(2 + 3*n + 3*n^2)/4.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5).
G.f.: f(x)/g(x), where f(x) = 2*x*(2 + 5*x + 2*x^2) and g(x) = (1-x)^5.
a(n) = Sum_{i=1..n} i*(3*i^2+1). - Bruno Berselli, Feb 09 2017
MATHEMATICA
(See A213822.)
PROG
(PARI) a(n) = n*(3*n^3 + 6*n^2 + 5*n + 2)/4 \\ Charles R Greathouse IV, Feb 09 2017
CROSSREFS
Cf. A213822.
Sequence in context: A027297 A211628 A166761 * A333277 A027445 A027789
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 04 2012
STATUS
approved