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A354233
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Least number with n runs in ordered prime signature.
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1
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1, 2, 12, 90, 2100, 48510, 3303300, 139369230, 18138420300, 1157182716690, 278261505822300, 30168910606824990, 9894144362523521100, 1693350783450479863710, 715178436956287675671300, 147157263134197051595990130, 83730945863531292204568790100
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OFFSET
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0,2
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COMMENTS
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A number's prime signature (row n of A124010) is the sequence of positive exponents in its prime factorization.
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LINKS
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EXAMPLE
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The prime indices of 90 are {1,2,2,3}, with multiplicities {1,2,1}, with runs {{1},{2},{1}}, and this is the first case of 3 runs, so a(3) = 90.
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MATHEMATICA
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Table[Product[Prime[i]^If[EvenQ[n-i], 1, 2], {i, n}], {n, 0, 15}]
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CROSSREFS
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Positions of first appearances in A353745.
A130091 lists numbers with distinct prime exponents, counted by A098859.
A323014 gives adjusted frequency depth of prime indices, counted by A325280.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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