|
|
A351366
|
|
a(n) = Sum_{p|n, p prime} p^p.
|
|
2
|
|
|
0, 4, 27, 4, 3125, 31, 823543, 4, 27, 3129, 285311670611, 31, 302875106592253, 823547, 3152, 4, 827240261886336764177, 31, 1978419655660313589123979, 3129, 823570, 285311670615, 20880467999847912034355032910567, 31, 3125, 302875106592257
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
FORMULA
|
G.f.: Sum_{k>=1} (prime(k) * x)^prime(k)/(1 - x^prime(k)). - Seiichi Manyama, Mar 02 2022
|
|
EXAMPLE
|
a(6) = 31; a(6) = Sum_{p|6, p prime} p^p = 2^2 + 3^3 = 31.
|
|
PROG
|
(PARI) my(N=40, x='x+O('x^N)); concat(0, Vec(sum(k=1, N, isprime(k)*(k*x)^k/(1-x^k)))) \\ Seiichi Manyama, Mar 02 2022
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|