A090553 Sigma(A090552(n)).

1, 3, 6, 12, 12, 24, 24, 24, 72, 72, 72, 72, 144, 144, 144, 144, 144, 288, 288, 288, 576, 576, 576, 576, 576, 576, 576, 576, 1152, 1152, 1152, 1152, 1152, 1152, 1152, 2304, 2304, 2304, 2304, 2304, 2304, 2304, 2304, 2304, 2304, 2304, 2304, 2304, 4608, 4608

Offset: 1

Author

Amarnath Murthy, Dec 09 2003

Keywords

• nonn

Crossrefs

Cf. A007368, A090552.

Programs

PARI

lista(nn) = {a = 1; print1(a, ", "); for (n = 1, nn, sa = sigma(a); a++; while (sigma(a) % sa, a++); print1(sigma(a), ", "););} \\ Michel Marcus, Oct 12 2013

Formula

a(n) = A000203(A090552(n)). - Michel Marcus, Oct 12 2013

Extensions

Corrected and extended by David Wasserman, Jan 04 2006