A134706 a(n) = n-th perfect number divided by 2^n, minus 1.

2, 6, 61, 507, 1048447, 134216703, 1073739775, 9007199250546687, 5192296858534827626278696515534847, 187072209578355573530071658285452771612302071824383

Offset

1,1

Links

Table of n, a(n) for n=1..10.

Formula

a(n)=(A000396(n)/(2^n)) - 1.

a(n) = A134705(n)-1. - R. J. Mathar, Jan 30 2008

Example

a(3)=61 because the 3rd perfect number is 496 and 2^3=8 and (496/8)-1=61.

Crossrefs

Cf. A000396, A133028.

Sequence in context: A139771 A129665 A173606 * A145756 A030170 A082640

Adjacent sequences: A134703 A134704 A134705 * A134707 A134708 A134709

Keyword

nonn

Author

Omar E. Pol, Nov 07 2007

Extensions

More terms from R. J. Mathar, Jan 30 2008

Status

approved