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%I #28 Jul 15 2015 18:02:44
%S 504,2394,5544,10584,12600,21600,26880,35712,133920,138240,139104,
%T 157248,168480,224640,245520,262080,294840,311040,348192,357120,
%U 388800,399168,645624,698544,749952,756000,892800,955206,1017792,1048320,1270080,1296000,1296000,1315440,1347840,1451520,1522800,1666560,1781136,1879200,2041200
%N The sum (in nondecreasing order) of the two numbers in an amicable pair.
%C Also the common value of sigma(x) = sigma(y) of the amicable pairs (x < y) ordered by nondecreasing sum (x + y). See A259933.
%C Duplicates occur, e.g., a(32) = a(33) = 1296000.
%C Another version of A180164.
%C First differs from both A161005 and A180164 at a(9).
%F a(n) = A259933(2n-1) + A259933(2n) = A260086(n) + A260087(n).
%e ------------------------------------------
%e A m i c a b l e p a i r Sum
%e ------------------------------------------
%e n A260086(n) + A260087(n) = a(n)
%e ------------------------------------------
%e 1 220 284 504
%e 2 1184 1210 2394
%e 3 2620 2924 5544
%e 4 5020 5564 10584
%e 5 6232 6368 12600
%e 6 10744 10856 21600
%e 7 12285 14595 26880
%e 8 17296 18416 35712
%e 9 66928 66992 133920
%e 10 67095 71145 138240
%e 11 63020 76084 139104
%e 12 69615 87633 157248
%e ... ... ... ...
%e 32 609928 686072 1296000
%e 33 643336 652664 1296000
%e ...
%Y Cf. A000203, A063990, A161005, A180164, A259180, A259933, A260086, A260087.
%K nonn
%O 1,1
%A _Omar E. Pol_, Jul 10 2015
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