A111904 Number of unitary amicable pairs in which the smallest member has n digits.

0, 0, 1, 1, 5, 12, 59, 107, 269, 641, 1457, 3553

Offset

1,5

Links

Table of n, a(n) for n=1..12.

J. O. M. Pedersen, Known Unitary Amicable Pairs

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]

Crossrefs

Cf. A002952, A002953.

Sequence in context: A131549 A342549 A346746 * A015784 A302182 A363452

Adjacent sequences: A111901 A111902 A111903 * A111905 A111906 A111907

Keyword

nonn,base

Author

N. J. A. Sloane, Nov 24 2005

Extensions

The next term, a(13), is at least 6664.

Status

approved