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

Author

Jaroslav Krizek, Jan 23 2014

Keywords

• nonn

Examples

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

Links

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

Crossrefs

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

Programs

Mathematica

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

PARI

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

Formula

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