A259302 Numbers n such that there exists an x!=n that makes {n,n,x} an amicable multiset.

1740, 7776, 19260, 20640, 21384, 21924, 22428, 25830, 31440, 55968, 93024, 101010, 106140, 143910, 151164, 198792, 246510, 309582, 326196, 411138, 421596, 428256, 499464, 590112, 639288, 697158, 870552, 941094, 958716, 1060956, 1068210, 1087776, 1100640

Offset

1,1

Comments

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

For the x values, see A259303.

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..1689

Prog

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

Crossrefs

Cf. A005820, A259307, A259303, A259304, A259305, A259306, A125490.

Sequence in context: A179160 A043653 A194775 * A251802 A251324 A184666

Adjacent sequences: A259299 A259300 A259301 * A259303 A259304 A259305

Keyword

nonn

Author

Jeppe Stig Nielsen, Jun 23 2015

Status

approved