A076084 Consider all numbers that can be formed by permuting the digits of n; take those with the greatest number of divisors; a(n) is the smallest of them.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 91, 20, 12, 22, 32, 24, 52, 26, 72, 28, 92, 30, 13, 32, 33, 34, 35, 36, 37, 38, 39, 40, 14, 24, 34, 44, 54, 64, 74, 84, 94, 50, 15, 52, 35, 54, 55, 56, 75, 58, 95, 60, 16, 26, 36, 64, 56, 66, 76, 68, 96, 70, 17, 72

Offset

1,2

Links

David A. Corneth, Table of n, a(n) for n = 1..10000 (First 1000 terms from Harvey P. Dale)

Example

a(24)=a(42) = 24. a(61) = 16.
From the numbers found by permuting the digits 1138, we get 1138, 1183, 1318, 1381, 1813, 1831, 3118, 3181, 3811, 8113, 8131 and 8311. We find that 8113 has the most divisors of those, namely 8. Therefore a(1138) = 8113. - David A. Corneth, Apr 22 2016

Mathematica

pdn[n_]:=Module[{c=SortBy[{#, DivisorSigma[0, #]}&/@FromDigits/@ Permutations[ IntegerDigits[n]], Last], m}, m=c[[-1, 2]]; Min[Transpose[ Select[c, #[[2]]==m&]][[1]]]]; Array[pdn, 80] (* Harvey P. Dale, Nov 29 2013 *)

Crossrefs

Cf. A261370.

Sequence in context: A358373 A285054 A090322 * A151764 A093618 A317257

Adjacent sequences: A076081 A076082 A076083 * A076085 A076086 A076087

Keyword

nonn,base,look

Author

Amarnath Murthy, Oct 07 2002

Extensions

More terms from David Wasserman, Mar 24 2005

Status

approved