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A363333 Numbers with a record number of divisors that are both coreful and bi-unitary. 1
1, 8, 32, 128, 216, 864, 3456, 7776, 13824, 31104, 108000, 279936, 432000, 972000, 1728000, 3888000, 15552000, 34992000, 62208000, 97200000, 139968000, 248832000, 333396000, 559872000, 592704000, 874800000, 1333584000, 5334336000, 12002256000, 21337344000, 33339600000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Indices of records in A363332.
The corresponding record values are 1, 3, 5, 7, 9, 15, 21, 25, 27, 35, 45, 49, 63, 75, 81, ... (see the link for more values).
LINKS
MATHEMATICA
f[p_, e_] := If[OddQ[e], e, e - 1]; d[1] = 1; d[n_] := Times @@ (f @@@ FactorInteger[n]); Array[a, 120]
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
Cf. A363332.
Subsequence of A025487.
Similar sequences: A005934, A293185.
Sequence in context: A269077 A183915 A357789 * A358253 A358252 A325839
KEYWORD
nonn
AUTHOR
Amiram Eldar, May 28 2023
STATUS
approved

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Last modified April 14 04:44 EDT 2024. Contains 371655 sequences. (Running on oeis4.)