A259303 - OEIS

A259303

Numbers n such that there exists an x!=n that makes {x,x,n} an amicable multiset.

1560, 7380, 20448, 20664, 22752, 23352, 25248, 26964, 35328, 51360, 100200, 104412, 108792, 135540, 156312, 192096, 232740, 252252, 278460, 310752, 362160, 401688, 492660, 543456, 548592, 588744, 659736, 732060, 767520, 826848, 998712, 999648, 1129440, 1129464

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OFFSET

1,1

COMMENTS

We call the multiset {x,x,n} amicable iff sigma(x)=sigma(n)=x+x+n.

For the x values, see A259302.

If the condition x!=n were dropped, the terms from A005820 would also belong here.

LINKS

John Cerkan, Table of n, a(n) for n = 1..1742

PROG

(PARI) isOK(n) = x=(sigma(n)-n)/2; x>0 && x!=n && denominator(x)==1 && sigma(x)==x+x+n;

CROSSREFS