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A262624 Even amicable numbers. 2
220, 284, 1184, 1210, 2620, 2924, 5020, 5564, 6232, 6368, 10744, 10856, 17296, 18416, 63020, 66928, 66992, 76084, 79750, 88730, 122368, 123152, 141664, 142310, 153176, 168730, 171856, 176272, 176336, 180848, 185368, 196724, 202444, 203432, 280540, 308620, 319550, 356408, 365084, 389924, 399592, 430402, 437456, 455344 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Even numbers that are also amicable numbers.

Intersection of A005843 and A063990.

The first time a pair (x, y) of even amicable numbers ordered by its first element is not adjacent is x = 63020, y = 76084 which correspond to a(15) and a(18), respectively.

LINKS

Table of n, a(n) for n=1..44.

PROG

(PARI) t(n)=sigma(n)-n;

is(n)={local(a); a=t(n); a<>n && t(a)==n};

for(n=1, 1e6, if( n%2 == 0 && is(n), print1(n", "))) \\ Altug Alkan, Oct 16 2015

CROSSREFS

Cf. A002025, A002046, A005843, A063990, A259180, A259933, A262625.

Sequence in context: A259180 A259933 A273259 * A262622 A287026 A233538

Adjacent sequences:  A262621 A262622 A262623 * A262625 A262626 A262627

KEYWORD

nonn

AUTHOR

Omar E. Pol, Oct 02 2015

STATUS

approved

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Last modified June 23 09:36 EDT 2018. Contains 305693 sequences. (Running on oeis4.)