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A361968
Unitary highly totient numbers: numbers k that have more solutions x to the equation uphi(x) = k than any smaller k, where uphi is the unitary totient function (A047994).
8
1, 6, 8, 12, 24, 48, 96, 120, 144, 240, 480, 576, 720, 1440, 2880, 4320, 5760, 8640, 10080, 17280, 20160, 30240, 34560, 40320, 60480, 80640, 120960, 241920, 362880, 483840, 725760, 967680, 1209600, 1451520, 2177280, 2419200, 2903040, 3628800, 4354560, 4838400
OFFSET
1,2
COMMENTS
Indices of records of A361967.
The corresponding numbers of solutions are 2, 3, 4, 5, 8, 11, ... (A361971).
LINKS
MATHEMATICA
solnum[n_] := Length[invUPhi[n]]; seq[kmax_] := Module[{s = {}, solmax=0}, Do[sol = solnum[k]; If[sol > solmax, solmax = sol; AppendTo[s, k]], {k, 1, kmax}]; s]; seq[10^5] (* using the function invUPhi from A361966 *)
CROSSREFS
The unitary version of A097942.
Sequence in context: A315873 A072057 A212351 * A327240 A274001 A324212
KEYWORD
nonn
AUTHOR
Amiram Eldar, Apr 01 2023
STATUS
approved