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A180163 Products of pairs of amicable numbers (see A063990). 2

%I #18 Oct 27 2017 19:53:15

%S 62480,1432640,7660880,27931280,39685376,116636864,179299575,

%T 318523136,4217802560,4494828240,4952759175,6067699000,7775676090,

%U 12285798525,15069863936,17358731325,20160203840,25845386480,30293400832

%N Products of pairs of amicable numbers (see A063990).

%C For a more reasonable sequence, in which both factors always belong to the same amicable pair, see A180202, which first differs from this sequence at a(9). - _Omar E. Pol_, Oct 25 2017

%F a(n) = A063990(2*n-1) * A063990(2*n).

%e a(1) = 220 * 284 = 62480 = 2^4 * 5 * 11 * 71.

%e a(2) = 1184 * 1210 = 1432640 = 2^6 * 5 * 11^2 * 37.

%Y Cf. A002025, A002046, A063990, A161005, A180202, A259180.

%K easy,nonn,less

%O 1,1

%A _Jonathan Vos Post_, Aug 14 2010

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Last modified May 12 22:37 EDT 2024. Contains 372497 sequences. (Running on oeis4.)