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A097211
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a(n) = the number of sets of distinct positive integers with a least common multiple of A025487(n), i.e., A076078(A025487(n)).
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2
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1, 2, 4, 10, 8, 44, 16, 184, 218, 32, 400, 752, 3748, 64, 3392, 3040, 61064, 128, 27904, 253808, 12224, 64594, 57856, 981520, 256, 226304, 16450240, 49024, 16700300, 954368, 15722528, 512, 1822720, 1055953664, 196352, 4278006328, 15499264
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OFFSET
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1,2
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COMMENTS
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The sequence A025487 contains the least number of each prime signature.
Sequence is a rearrangement of A097210 unless two or more members of A025487 are LCMs of an identical number of sets of distinct positive integers.
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LINKS
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MATHEMATICA
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f[n_] := Block[{d = Divisors[n]}, Plus @@ (MoebiusMu[n/d](2^DivisorSigma[0, d] - 1))]; PrimeExponents[n_] := Flatten[ Table[ # [[2]], {1}] & /@ FactorInteger[n]]; lpe = {}; ln = {1}; Do[pe = Sort[PrimeExponents[n]]; If[ Position[lpe, pe] == {}, AppendTo[lpe, pe]; AppendTo[ln, f[n]]], {n, 1000}]; ln (* Robert G. Wilson v, Aug 14 2004 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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