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 A332043 Indices of records in A332042. 1
 1, 6, 12, 24, 48, 72, 144, 288, 576, 864, 1152, 1440, 1728, 2160, 2304, 2880, 4320, 5760, 8640, 17280, 25920, 34560, 51840, 69120, 103680, 120960, 138240, 155520, 181440, 207360, 241920, 311040, 362880, 414720, 483840, 622080, 725760, 967680, 1244160, 1451520 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numbers k such that psi(x) = k has more solutions x than any smaller k, where psi(x) is the Dedekind psi function (A001615). The corresponding number of solutions for each term is 1, 2, 4, 5, 6, 9, 11, 17, ... (see the link for more values). LINKS Amiram Eldar, Table of n, a(n) for n = 1..59 Amiram Eldar, Table of n, a(n), A332042(a(n)) for n = 1..59 EXAMPLE There are 2 solutions to psi(x) = 6: psi(4) = psi(5) = 6. For all m < 6 there are no more than one solution to psi(x) = m, thus 6 is in the sequence. MATHEMATICA psi[1] = 1; psi[n_] := n * Times @@ (1 + 1/Transpose[FactorInteger[n]][[1]]); m = 10000; v = Table[0, {m}]; Do[i = psi[k]; If[i <= m, v[[i]]++], {k, 1, m}]; s = {}; vm = -1; Do[If[v[[k]] > vm, vm = v[[k]]; AppendTo[s, k]], {k, 1, m}]; s CROSSREFS Cf. A001615, A145899, A289132, A332037, A332039, A332041, A332042. Sequence in context: A331200 A212116 A160728 * A362487 A229926 A082505 Adjacent sequences: A332040 A332041 A332042 * A332044 A332045 A332046 KEYWORD nonn AUTHOR Amiram Eldar, Feb 05 2020 STATUS approved

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Last modified February 23 06:06 EST 2024. Contains 370267 sequences. (Running on oeis4.)