A213850 Antidiagonal sums of the convolution array A213849.

1, 3, 10, 20, 42, 70, 120, 180, 275, 385, 546, 728, 980, 1260, 1632, 2040, 2565, 3135, 3850, 4620, 5566, 6578, 7800, 9100, 10647, 12285, 14210, 16240, 18600, 21080, 23936, 26928, 30345, 33915, 37962, 42180, 46930

Offset

1,2

Links

Clark Kimberling, Table of n, a(n) for n = 1..500

Index entries for linear recurrences with constant coefficients, signature (2,2,-6,0,6,-2,-2,1).

Formula

a(n) = (n + 1)*(n + 2)*(3 - 3*(-1)^n + 8*n + 2*n^2)/96.

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) = x*(1 + x + 2*x^2) and g(x) = (1+x)^3*(1-x)^5.

Mathematica

(See A213849.)

Crossrefs

Cf. A213849.

Sequence in context: A293765 A295953 A005997 * A336529 A081205 A273379

Adjacent sequences: A213847 A213848 A213849 * A213851 A213852 A213853

Keyword

nonn,easy

Author

Clark Kimberling, Jul 05 2012

Status

approved