A066476 Numbers having just ten anti-divisors.

162, 220, 221, 225, 242, 313, 365, 392, 512, 545, 613, 648, 676, 840, 900, 1089, 1201, 1301, 1352, 1404, 1521, 1600, 1682, 1741, 2113, 2244, 2381, 2665, 3120, 3281, 3444, 3445, 3872, 3961, 4324, 4356, 4489, 4608, 4761, 5832, 5941, 6161, 6384, 6561, 6724

Offset

1,1

Comments

See A066272 for definition of anti-divisor.

Links

Table of n, a(n) for n=1..45.

Jon Perry, The Anti-Divisor

Jon Perry, The Anti-divisor [Cached copy]

Jon Perry, The Anti-divisor: Even More Anti-Divisors [Cached copy]

Mathematica

antid[n_] := Select[ Union[ Join[ Select[ Divisors[2n - 1], OddQ[ # ] && # != 1 & ], Select[ Divisors[2n + 1], OddQ[ # ] && # != 1 & ], 2n/Select[ Divisors[ 2*n], OddQ[ # ] && # != 1 &]]] }, # < n & ]]; Select[ Range[10^4], Length[ antid[ # ]] == 10 & ]

Crossrefs

Cf. A066272.

Sequence in context: A025374 A025365 A045227 * A259220 A107120 A045010

Adjacent sequences: A066473 A066474 A066475 * A066477 A066478 A066479

Keyword

nonn

Author

Robert G. Wilson v, Jan 02 2002

Status

approved