A213780 Antidiagonal sums of the convolution array A213778.

1, 6, 17, 40, 78, 140, 230, 360, 535, 770, 1071, 1456, 1932, 2520, 3228, 4080, 5085, 6270, 7645, 9240, 11066, 13156, 15522, 18200, 21203, 24570, 28315, 32480, 37080, 42160, 47736, 53856, 60537, 67830, 75753, 84360, 93670, 103740, 114590

Offset

1,2

Links

Clark Kimberling, Table of n, a(n) for n = 1..1000

Index entries for linear recurrences with constant coefficients, signature (3,-1,-5,5,1,-3,1).

Formula

a(n) = 3*a(n-1) - a(n-2) - 5*a(n-3) + 5*a(n-4) + a(n-5) - 3*a(n-6) + a(n-7).

G.f.: f(x)/g(x), where f(x) = x*(1 + 3*x) and g(x) = (1 + x)^2 *(1 - x)^5.

Mathematica

(See A213778.)

Crossrefs

Cf. A213778, A213500.

Sequence in context: A366104 A080275 A061349 * A101945 A220407 A013319

Adjacent sequences: A213777 A213778 A213779 * A213781 A213782 A213783

Keyword

nonn,easy

Author

Clark Kimberling, Jun 21 2012

Status

approved