A236287 a(n) = sigma(n)^tau(n), where tau(n) = A000005(n) = the number of divisors of n and sigma(n) = A000203(n) = the sum of divisors of n.

1, 9, 16, 343, 36, 20736, 64, 50625, 2197, 104976, 144, 481890304, 196, 331776, 331776, 28629151, 324, 3518743761, 400, 5489031744, 1048576, 1679616, 576, 167961600000000, 29791, 3111696, 2560000, 30840979456, 900, 722204136308736, 1024, 62523502209, 5308416

Offset

1,2

Links

Jaroslav Krizek, Table of n, a(n) for n = 1..100

Formula

a(n) = A000203(n)^A000005(n).

Example

a(4) = sigma(4)^tau(4) = 7^3 = 343.

Mathematica

Table[DivisorSigma[1, n]^DivisorSigma[0, n], {n, 1000}]

Prog

(PARI) s=[]; for(n=1, 40, s=concat(s, sigma(n, 1)^sigma(n, 0))); s \\ Colin Barker, Jan 24 2014

Crossrefs

Cf. A000005 (tau(n)), A000203 (sigma(n)), A062758 (n^tau(n)), A217872 (sigma(n)^n), A236285 (tau(n)^sigma(n)), A236286.

Sequence in context: A072470 A053911 A171522 * A329964 A050802 A264519

Adjacent sequences: A236284 A236285 A236286 * A236288 A236289 A236290

Keyword

nonn

Author

Jaroslav Krizek, Jan 23 2014

Status

approved