OFFSET
0,2
COMMENTS
Antidiagonal sums of the convolution array A213825.
LINKS
Clark Kimberling, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).
FORMULA
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5).
G.f.: x*(2 + 11*x + 5*x^2) / (1-x)^5.
a(n) = Sum_{i=1..n} i*(n^2+i^2). - Bruno Berselli, Aug 25 2014
EXAMPLE
a(7) = 1*(7^2+1) + 2*(7^2+2^2) + 3*(7^2+3^2) + 4*(7^2+4^2) + 5*(7^2+5^2) + 6*(7^2+6^2) + 7*(7^2+7^2) = 2156. [Bruno Berselli, Aug 25 2014]
MATHEMATICA
(See A213825.)
PROG
(Magma) [(n+1)*(3*n+1)*n^2/4: n in [1..40]]; // Bruno Berselli, Aug 25 2014
(Sage) [(n+1)*(3*n+1)*n^2/4 for n in (1..40)] # Bruno Berselli, Aug 25 2014
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Jul 04 2012
EXTENSIONS
Edited by N. J. A. Sloane, May 14 2020 (changed offset, changed to simpler definition from Bruno Berselli).
STATUS
approved