|
|
A034667
|
|
Sum of n-th powers of divisors of 40.
|
|
3
|
|
|
8, 90, 2210, 73710, 2734994, 105736950, 4161281930, 165132191790, 6579317233634, 262657136433510, 10496011084557050, 419635308642959070, 16781313068980398674, 671170570551043634070, 26845184104404418478570, 1073774593035215963441550
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,1
|
|
LINKS
|
|
|
FORMULA
|
G.f.: -2*(2880000*x^7 -4712000*x^6 +2797200*x^5 -793128*x^4 +116550*x^3 -8835*x^2 +315*x -4) / ((x -1)*(2*x -1)*(4*x -1)*(5*x -1)*(8*x -1)*(10*x -1)*(20*x -1)*(40*x -1)). - Colin Barker, May 03 2014
a(n) = 90*a(n-1)-2945*a(n-2)+46620*a(n-3)-396564*a(n-4)+1864800*a(n-5)-4712000*a(n-6)+5760000*a(n-7)-2560000*a(n-8). - Wesley Ivan Hurt, Oct 23 2014
|
|
MAPLE
|
|
|
MATHEMATICA
|
|
|
PROG
|
(Magma) [&+[Divisors(40)[i]^n: i in [1..8]]: n in [0..20]]; // Vincenzo Librandi, Apr 17 2014
(PARI) vector(30, n, sigma(40, n-1)) \\ Colin Barker, May 03 2014
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|