|
| |
|
|
A367551
|
|
a(n) = Sum_{d|n} (d^2+1)^n.
|
|
1
|
|
|
|
2, 29, 1008, 84162, 11881408, 2566742098, 781250000128, 318651789038947, 167619551409708544, 110462353708225871026, 89116503268220597579776, 86380568889558343409300388, 99045780329059370000000008192
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
LINKS
|
|
|
|
FORMULA
|
a(n) = Sum_{k=0..n} binomial(n,k) * sigma_{2*k}(n).
|
|
|
PROG
|
(PARI) a(n) = sumdiv(n, d, (d^2+1)^n);
|
|
|
CROSSREFS
|
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
|
|
|
STATUS
|
approved
|
| |
|
|
