|
|
A231307
|
|
Recurrence a(n) = a(n-2) + n^M for M=8, starting with a(0)=0, a(1)=1.
|
|
7
|
|
|
0, 1, 256, 6562, 65792, 397187, 1745408, 6161988, 18522624, 49208709, 118522624, 263567590, 548504320, 1079298311, 2024293376, 3642188936, 6319260672, 10617946377, 17339221248, 27601509418, 42939221248, 65424368779, 97815094784, 143735354060
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
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
|
|
|
STATUS
|
approved
|
|
|
|