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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
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
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
Sequence in context: A226265 A277114 A269038 * A259953 A180164 A263286
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