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Numbers that have more cubefree divisors than any smaller number.
2

%I #10 Oct 18 2024 20:26:52

%S 1,2,4,6,12,30,36,60,180,420,900,1260,4620,6300,13860,44100,60060,

%T 69300,180180,485100,900900,3063060,6306300,15315300,58198140,

%U 107207100,290990700,1179278100,1338557220,2036934900,6692786100,22406283900,38818159380,46849502700,194090796900

%N Numbers that have more cubefree divisors than any smaller number.

%C First differ from A333931 and A353899 at n = 17.

%C Indices of records in A073184.

%C The corresponding record values are 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 27, 36, 48, 54, 72, 81, 96, 108, ... (see the link for more values).

%H Amiram Eldar, <a href="/A377139/b377139.txt">Table of n, a(n) for n = 1..140</a>

%H Amiram Eldar, <a href="/A377139/a377139.txt">Table of n, a(n), A073184(a(n)) for n = 1..140</a>

%t f[p_, e_] := If[e == 1, 2, 3]; d[1] = 1; d[n_] := Times @@ f @@@ FactorInteger[n]; With[{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]

%Y Subsequence of A004709 and A025487.

%Y Cf. A004709, A073184, A333931, A353899, A377140.

%K nonn

%O 1,2

%A _Amiram Eldar_, Oct 17 2024