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 A134706 a(n) = n-th perfect number divided by 2^n, minus 1. 0
 2, 6, 61, 507, 1048447, 134216703, 1073739775, 9007199250546687, 5192296858534827626278696515534847, 187072209578355573530071658285452771612302071824383 (list; graph; refs; listen; history; text; internal format)
 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

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Last modified May 21 00:14 EDT 2024. Contains 372720 sequences. (Running on oeis4.)