A351252 a(n) = sigma(n) * A276086(n), pointwise product of the sum of divisors function and the primorial base exp-function.

2, 9, 24, 63, 108, 60, 80, 225, 390, 810, 1080, 700, 700, 1800, 3600, 6975, 8100, 4875, 5000, 15750, 24000, 40500, 54000, 37500, 38750, 78750, 150000, 315000, 337500, 504, 448, 1323, 2016, 3402, 6048, 3185, 2660, 6300, 11760, 28350, 26460, 16800, 15400, 44100, 81900, 113400, 151200, 108500, 99750, 244125, 378000

Offset: 1

Author

Antti Karttunen, Feb 17 2022

Keywords

• nonn

Links

• Index entries for sequences related to primorial base
• Index entries for sequences related to sigma(n)

Crossrefs

Cf. A000203, A276086.

Cf. also A324580, A341529, A351458.

Programs

Mathematica

Array[Block[{i = 1, m = 1, n = #, p}, While[n > 0, p = Prime[i]; m *= p^Mod[n, p]; n = Quotient[n, p]; i++]; DivisorSigma[1, #]*m] &, 51] (* Michael De Vlieger, Feb 17 2022, after Jean-François Alcover at A276086 *)

PARI

A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
A351252(n) = (sigma(n) * A276086(n));

Formula

a(n) = A000203(n) * A276086(n).