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A161005 Sums of adjacent amicable numbers, a(n) = A063990(2n-1) + A063990(2n). 9
504, 2394, 5544, 10584, 12600, 21600, 26880, 35712, 129948, 134087, 140760, 155834, 176363, 222750, 245520, 263970, 283974, 321906, 348128, 357184, 382092, 405876, 589160, 675958, 755008, 829994, 892800, 955206, 1017792, 1048320 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Warning: The numbers being summed will not always belong to the same amicable pair. See A180164 for the sums of amicable pairs. - Jeppe Stig Nielsen, Jan 27 2015

LINKS

T. D. Noe, Table of n, a(n) for n=1..1000

EXAMPLE

a(1) = 504 = 220 + 284.

a(2) = 2394 = 1184 + 1210.

a(3) = 5544 = 2620 + 2694.

MATHEMATICA

s[n_] := DivisorSigma[1, n] - n;

AmicableNumberQ[n_] := If[Nest[s, n, 2] == n && ! s[n] == n, True, False];

a = Select[Range[10^6], AmicableNumberQ[ # ] &];

Table[a[[n + 1]] + a[[n]], {n, 1, Length[a], 2}]

(* Roger L. Bagula, May 29 2010, based on Ant King's Mathematica program from A063990 *)

CROSSREFS

Cf. A063990, A259180.

Sequence in context: A226265 A277114 A269038 * A259953 A180164 A263286

Adjacent sequences:  A161002 A161003 A161004 * A161006 A161007 A161008

KEYWORD

nonn,less

AUTHOR

Claudio Meller, Jun 01 2009

EXTENSIONS

Corrected and extended by Roger L. Bagula, May 29 2010

Edited by N. J. A. Sloane, Aug 14 2010, at the suggestion of Jason G. Wurtzel

STATUS

approved

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Last modified June 1 04:57 EDT 2020. Contains 334758 sequences. (Running on oeis4.)