A134706 - OEIS

%I #4 Mar 30 2012 17:39:27

%S 2,6,61,507,1048447,134216703,1073739775,9007199250546687,

%T 5192296858534827626278696515534847,

%U 187072209578355573530071658285452771612302071824383

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

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

%F a(n) = A134705(n)-1. - _R. J. Mathar_, Jan 30 2008

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

%Y Cf. A000396, A133028.

%K nonn

%O 1,1

%A _Omar E. Pol_, Nov 07 2007

%E More terms from _R. J. Mathar_, Jan 30 2008