login
A153487
Sum of first n perfect numbers A000396, divided by 2.
0
3, 17, 265, 4329, 16779497, 4311714025, 73031059689, 1152921577101035753, 1329227995784915873480267885077956841, 95780971304118054976624684827067692545766545852041449
OFFSET
1,1
COMMENTS
Partial sums of A133028. [From R. J. Mathar, Jan 21 2009]
FORMULA
a(n) = A092336(n)/2.
MATHEMATICA
Accumulate[(# (#+1))/2&/@Select[2^Range[90]-1, PrimeQ] ]/2 (* Harvey P. Dale, Sep 04 2014 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Omar E. Pol, Dec 27 2008
EXTENSIONS
More terms from R. J. Mathar, Jan 21 2009
STATUS
approved