A000173 Unitary-sociable numbers (smallest member of each cycle).

30, 1482, 2418, 24180, 35238, 263820, 395730, 473298, 698130, 763620, 2212026, 2233554, 172459210, 209524210, 341354790, 384121920, 525150234, 530946330, 582129630, 1799281330, 2069510520, 2514290520, 3344596854, 5251502340

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• nice

Comments

If n=product p_i^a_i, d=product p_i^c_i is a unitary divisor of n if each c_i is 0 or a_i.

References

• R. K. Guy, Unsolved Problems in Number Theory, 3rd edition, Sect. B7.

Links

• Herman Jamke (hermanjamke(AT)fastmail.fm), Nov 01 2006, Table of n, a(n) for n = 1..44
• David Moews, Perfect, amicable and sociable numbers.
• J. O. M. Pedersen, Tables of Aliquot Cycles. [Broken link]
• J. O. M. Pedersen, Tables of Aliquot Cycles. [Via Internet Archive Wayback-Machine]
• J. O. M. Pedersen, Tables of Aliquot Cycles. [Cached copy, pdf file only]
• Eric Weisstein's World of Mathematics, Sociable Numbers.

Crossrefs

Cf. A034444, A003416, A097323.

Extensions

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Nov 01 2006