A153800 Indices of perfect numbers (A000396) in the sequence of multiply-perfect numbers (A007691).

2, 3, 5, 7, 13, 19, 25, 41, 110, 192, 229, 294

Offset

1,1

Comments

The sequence contains no further entries between 294 and 1600. - R. J. Mathar, May 26 2011

Links

Table of n, a(n) for n=1..12.

Example

a(7) is 25 because the 25th multiply-perfect number A007691(25)=137438691328 is also the 7th perfect number A000396(7).

Crossrefs

Cf. A000396, A007691.

Sequence in context: A233043 A231099 A062252 * A362777 A147791 A169647

Adjacent sequences: A153797 A153798 A153799 * A153801 A153802 A153803

Keyword

more,nonn

Author

Omar E. Pol, Jan 13 2009

Status

approved