OFFSET
1,2
LINKS
Harry J. Smith, Table of n, a(n) for n=1..1000
Index entries for linear recurrences with constant coefficients, signature (6,-15,20,-15,6,-1).
FORMULA
a(n) = n*(6*n^4 + 10*n^2 - 1)/15. - Dean Hickerson, Jun 06 2001
G.f.: x*(1+x)^2*(1+10*x+x^2)/(1-x)^6. - Colin Barker, Apr 20 2012
E.g.f.: exp(x)*x*(15 + 120*x + 160*x^2 + 60*x^3 + 6*x^4)/15. - Stefano Spezia, Dec 08 2024
EXAMPLE
a(3) = 115 = 1 + 16 + 81 + 16 + 1
MATHEMATICA
Table[Total[2Range[n-1]^4]+n^4, {n, 30}] (* or *) LinearRecurrence[{6, -15, 20, -15, 6, -1}, {1, 18, 115, 452, 1333, 3254}, 30] (* Harvey P. Dale, Aug 23 2016 *)
PROG
(PARI) a(n) = { n*(6*n^4 + 10*n^2 - 1)/15 } \\ Harry J. Smith, Jul 28 2009
CROSSREFS
KEYWORD
nonn,easy,changed
AUTHOR
Amarnath Murthy, May 28 2001
EXTENSIONS
More terms from Larry Reeves (larryr(AT)acm.org) and Jason Earls, May 28 2001
STATUS
approved