A259953 The sum (in nondecreasing order) of the two numbers in an amicable pair.

504, 2394, 5544, 10584, 12600, 21600, 26880, 35712, 133920, 138240, 139104, 157248, 168480, 224640, 245520, 262080, 294840, 311040, 348192, 357120, 388800, 399168, 645624, 698544, 749952, 756000, 892800, 955206, 1017792, 1048320, 1270080, 1296000, 1296000, 1315440, 1347840, 1451520, 1522800, 1666560, 1781136, 1879200, 2041200

Offset: 1

Author

Omar E. Pol, Jul 10 2015

Keywords

• nonn

Comments

Also the common value of sigma(x) = sigma(y) of the amicable pairs (x < y) ordered by nondecreasing sum (x + y). See A259933.

Duplicates occur, e.g., a(32) = a(33) = 1296000.

Another version of A180164.

First differs from both A161005 and A180164 at a(9).

Examples

			------------------------------------------
      A m i c a b l e   p a i r      Sum
------------------------------------------
n     A260086(n)  +  A260087(n)  =   a(n)
------------------------------------------
1         220            284          504
2        1184           1210         2394
3        2620           2924         5544
4        5020           5564        10584
5        6232           6368        12600
6       10744          10856        21600
7       12285          14595        26880
8       17296          18416        35712
9       66928          66992       133920
10      67095          71145       138240
11      63020          76084       139104
12      69615          87633       157248
...       ...            ...          ...
32     609928         686072      1296000
33     643336         652664      1296000
...
		

Crossrefs

Cf. A000203, A063990, A161005, A180164, A259180, A259933, A260086, A260087.

Formula

a(n) = A259933(2n-1) + A259933(2n) = A260086(n) + A260087(n).