OFFSET
0,3
LINKS
Stanislav Sykora, Table of n, a(n) for n = 0..9999
Stanislav Sýkora, Magnetic Resonance on OEIS, Stan's NMR Blog (Dec 31, 2014), Retrieved Nov 12, 2019.
Index entries for linear recurrences with constant coefficients, signature (10,-45,120,-210,252,-210,120,-45,10,-1).
FORMULA
a(n) = Sum_{k=0..floor(n/2)} (n-2k)^8.
a(n) = 1/90*n*(n+1)*(n+2)*(5*n^6+30*n^5+20*n^4-120*n^3-16*n^2+288*n-192). - Vaclav Kotesovec, Feb 14 2014
G.f.: x*(1+246*x+4047*x^2+11572*x^3+4047*x^4+246*x^5+x^6) / (1-x)^10.
EXAMPLE
a(5) = 5^8 + 3^8 + 1^8 = 397187.
MATHEMATICA
Table[1/90*n*(n+1)*(n+2)*(5*n^6+30*n^5+20*n^4-120*n^3-16*n^2+288*n-192), {n, 0, 20}] (* Vaclav Kotesovec, Feb 14 2014 *)
PROG
(PARI) nmax=100; a = vector(nmax); a[2]=1; for(i=3, #a, a[i]=a[i-2]+(i-1)^8); print(a);
(PARI) concat(0, Vec(x*(1+246*x+4047*x^2+11572*x^3+4047*x^4+246*x^5+x^6)/(1-x)^10 + O(x^50))) \\ Colin Barker, Dec 22 2015
(Magma) [1/90*n*(n+1)*(n+2)*(5*n^6+30*n^5+20*n^4-120*n^3-16*n^2+288*n-192): n in [0..30]]; // Vincenzo Librandi, Dec 23 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Stanislav Sykora, Nov 07 2013
STATUS
approved