A224440 a(n) = sigma(n)^(n-1).

1, 3, 16, 343, 1296, 248832, 262144, 170859375, 815730721, 198359290368, 61917364224, 8293509467471872, 56693912375296, 876488338465357824, 21035720123168587776, 23465261991844685929951, 121439531096594251776, 1117116121846700839825703079, 262144000000000000000000

Offset

1,2

Comments

Here sigma(n) = A000203(n) is the sum of the divisors of n.

Links

Seiichi Manyama, Table of n, a(n) for n = 1..335

Formula

Logarithmic derivative of A224439.

Example

L.g.f.: L(x) = x + 3^1*x^2/2 + 4^2*x^3/3 + 7^3*x^4/4 + 6^4*x^5/5 + 12^5*x^6/6 +...
where exponentiation yields the g.f. of A224439:
exp(L(x)) = 1 + x + 2*x^2 + 7*x^3 + 93*x^4 + 357*x^5 + 41927*x^6 +...

Prog

(PARI) {a(n)=sigma(n)^(n-1)}
for(n=1, 20, print1(a(n), ", "))

Crossrefs

Cf. A224439, A217872.

Sequence in context: A053466 A005031 A300960 * A054939 A081782 A176299

Adjacent sequences: A224437 A224438 A224439 * A224441 A224442 A224443

Keyword

nonn

Author

Paul D. Hanna, Apr 06 2013

Extensions

Offset corrected by Seiichi Manyama, Nov 10 2017

Status

approved