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A347399
a(n) = A347398(n^n).
1
1, 5, 28, 261, 3126, 46688, 823544, 16777477, 387420517, 10000003386, 285311670612, 8916117272416, 302875106592254, 11112006826381820, 437893890380862528, 18446744073726329093, 827240261886336764178, 39346408075296925042857
OFFSET
1,2
COMMENTS
This sequence is different from A062796.
FORMULA
a(n) = A347397(n^n) - A347397(n^n-1) for n > 1.
a(n) = Sum_{k=1..n, k^k | n^n} k^k.
If p is prime, a(p) = 1 + p^p.
PROG
(PARI) a(n) = sum(k=1, n, (n^n%k^k==0)*k^k);
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 30 2021
STATUS
approved