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 A134705 a(n) = n-th perfect number divided by 2^n. 2
 3, 7, 62, 508, 1048448, 134216704, 1073739776, 9007199250546688, 5192296858534827626278696515534848, 187072209578355573530071658285452771612302071824384 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..10. Omar E. Pol, Determinacion geometrica de los numeros primos y perfectos. FORMULA a(n)=A000396(n)/(2^n). EXAMPLE a(3)=62 because the 3rd perfect number is 496 and 2^3=8 and 496/8=62. MAPLE perfp := [1, 2, 4, 6, 12, 16, 18, 30, 60, 88, 106, 126, 520, 606, 1278, 2202, 2280, 3216, 4252] : A000396 := proc(n) global perfp ; 2^op(n, perfp)*(2^(op(n, perfp)+1)-1) ; end: A134705 := proc(n) A000396(n)/2^n ; end: seq(A134705(n), n=1..12) ; # R. J. Mathar CROSSREFS Cf. A000396, A133028. Sequence in context: A258184 A362347 A077703 * A110433 A219845 A041817 Adjacent sequences: A134702 A134703 A134704 * A134706 A134707 A134708 KEYWORD nonn AUTHOR Omar E. Pol, Nov 07 2007 EXTENSIONS More terms from R. J. Mathar, Jan 07 2008 STATUS approved

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Last modified June 19 17:03 EDT 2024. Contains 373504 sequences. (Running on oeis4.)