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A377138
Powerful numbers that have more divisors than any smaller powerful number.
1
1, 4, 8, 16, 32, 36, 72, 144, 216, 288, 432, 576, 864, 900, 1728, 1800, 3600, 5400, 7200, 10800, 14400, 21600, 32400, 43200, 64800, 86400, 88200, 176400, 264600, 352800, 529200, 705600, 1058400, 1587600, 2116800, 3175200, 4233600, 6350400, 8467200, 10584000, 12700800
OFFSET
1,2
COMMENTS
First differs from A283052 at n = 12.
Indices of records in A357669.
The corresponding record values are 1, 3, 4, 5, 6, 9, 12, 15, 16, 18, 20, 21, 24, 27, 28, 36, ... (see the link for more values).
MATHEMATICA
f[p_, e_] := If[e == 1, 1, e + 1]; 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]
CROSSREFS
Subsequence of A001694 and A025487.
Sequence in context: A304250 A368681 A322793 * A283052 A088259 A123857
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 17 2024
STATUS
approved