A368252 Numbers with a record value of number of uniform divisors (A327527).

1, 2, 4, 6, 12, 24, 30, 60, 120, 180, 210, 420, 840, 1260, 2310, 4620, 9240, 13860, 27720, 30030, 60060, 120120, 180180, 360360, 510510, 1021020, 2042040, 3063060, 6126120, 9699690, 19399380, 38798760, 58198140, 116396280, 223092870, 446185740, 892371480, 1338557220

Offset: 1

Author

Amiram Eldar, Dec 19 2023

Keywords

• nonn

Comments

First differs from A346016 at n = 48, and from A282472 at n = 155.

Examples

			The sequence A327527 starts with 1, 2, 2, 3, 2, 4, 2, 4, 3, 4, 2, 5, ... . The record values, 1, 2, 3, 4 and 5, occur at indices 1, 2, 4, 6, 12, the first 5 terms of this sequence.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..212
• Amiram Eldar, Table of n, a(n), A327527(a(n)) for n = 1..212

Crossrefs

Cf. A282472, A327527, A346016.

Subsequence of A025487.

Programs

Mathematica

d[n_] := Module[{e = FactorInteger[n][[;; , 2]]}, 1 + Total[2^Accumulate[Count[e, #] & /@ Range[Max[e], 1, -1]] - 1]]; d[1] = 1;
v = Cases[Import["https://oeis.org/A025487/b025487.txt", "Table"], {, }][[;; , 2]];
seq = {}; dm = 0; Do[If[(dk = d[v[[k]]]) > dm, dm = dk; AppendTo[seq, v[[k]]]], {k, 1, Length[v]}]; seq