A319937 Unitary sociable numbers of order 10.

525150234, 527787366, 528544218, 553128198, 612951066, 675192294, 735821562, 982674438, 998151162, 998151174, 5251502340, 5277873660, 5285442180, 5531281980, 6129510660, 6751922940, 7358215620, 9826744380, 9981511620, 9981511740

Offset: 1

Author

Michel Marcus, Oct 02 2018

Keywords

• nonn
• more

Links

• J. O. M. Pedersen, Known Unitary Sociable Numbers of order different from four [Via Internet Archive Wayback-Machine]
• Eric Weisstein's World of Mathematics, Unitary Sociable Numbers
• J. O. M. Pedersen, Order 10 cycles

Crossrefs

Cf. A063919 (sum of proper unitary divisors).

Cf. A002827 (unitary perfect), A063991 (unitary amicable).

Cf. A097024 (order 5), A319917 (order 6), A097030 (order 14).

Programs

PARI

f(n) = sumdiv(n, d, if(gcd(d, n/d)==1, d)) - n;
isok10(n) = iferr(f(f(f(f(f(f(f(f(f(f(n)))))))))) == n, E, 0);
isok5(n) = iferr(f(f(f(f(f(n))))) == n, E, 0);
isok2(n) = iferr(f(f(n)) == n, E, 0);
isok1(n) = iferr(f(n) == n, E, 0);
isok(n) = isok10(n) && !isok1(n) && !isok2(n) && !isok5(n);