A180163 - OEIS

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A180163

Products of pairs of amicable numbers (see A063990).

62480, 1432640, 7660880, 27931280, 39685376, 116636864, 179299575, 318523136, 4217802560, 4494828240, 4952759175, 6067699000, 7775676090, 12285798525, 15069863936, 17358731325, 20160203840, 25845386480, 30293400832

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

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

LINKS

Table of n, a(n) for n=1..19.

FORMULA

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

EXAMPLE

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

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

CROSSREFS

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

Sequence in context: A181114 A242620 A203046 * A180202 A031659 A257150

Adjacent sequences: A180160 A180161 A180162 * A180164 A180165 A180166

KEYWORD

easy,nonn,less

AUTHOR

Jonathan Vos Post, Aug 14 2010

STATUS

approved