A358101 Positions of records in A358099, i.e., integers whose number of divisors whose decimal digits are in strictly decreasing order sets a new record.

1, 2, 4, 6, 12, 20, 30, 40, 60, 120, 240, 360, 420, 840, 1260, 2520, 5040, 8640, 10080, 15120, 20160, 30240, 60480, 120960, 181440, 362880, 544320, 786240, 1572480, 1874880, 3749760, 5624640, 7862400, 14938560, 23587200, 24373440, 31872960, 63745920, 95618880

Offset

1,2

Comments

As A009995 is finite, this sequence is necessarily finite.

Corresponding records are 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, ...

Links

Table of n, a(n) for n=1..39.

Example

a(9) = 60 is in the sequence because A358099(60) = 10 is larger than any earlier value in A358099.

Mathematica

f[n_] := DivisorSum[n, 1 &, Greater @@ IntegerDigits[#] &]; fm = 0; s = {}; Do[If[(fn = f[n]) > fm, fm = fn; AppendTo[s, n]], {n, 1, 10^6}]; s (* Amiram Eldar, Nov 03 2022 *)

Crossrefs

Cf. A009995, A190219, A358099, A358100.

Similar sequences: A093036, A340548, A357173.

Sequence in context: A370638 A331872 A307067 * A358100 A060798 A134320

Adjacent sequences: A358098 A358099 A358100 * A358102 A358103 A358104

Keyword

nonn,base,fini

Author

Bernard Schott, Nov 03 2022

Extensions

More terms from Amiram Eldar, Nov 03 2022

Status

approved