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A088860
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Twice the primorials (first definition), 2*A002110(n).
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8
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4, 12, 60, 420, 4620, 60060, 1021020, 19399380, 446185740, 12939386460, 401120980260, 14841476269620, 608500527054420, 26165522663340060, 1229779565176982820, 65178316954380089460, 3845520700308425278140
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OFFSET
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1,1
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COMMENTS
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Also, least number m divisible by 4 such that omega(m)=n, where omega=A001221.
Refers to the least number which is the leg of exactly 2^(n-1) primitive Pythagorean triangles.
For n >= 1, a(n) = A097250(n). - G. C. Greubel, Apr 23 2017
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LINKS
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G. C. Greubel, Table of n, a(n) for n = 1..345
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FORMULA
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a(n) = 2*#p(n) = 2*A002110(n).
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MATHEMATICA
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2*FoldList[Times, 1, Prime[Range[50]]] (* G. C. Greubel, Apr 23 2017 *)
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CROSSREFS
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Cf. A002110, A001221, A097250.
Sequence in context: A324693 A276707 A083484 * A097250 A188328 A291772
Adjacent sequences: A088857 A088858 A088859 * A088861 A088862 A088863
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KEYWORD
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nonn
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AUTHOR
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Lekraj Beedassy, Nov 25 2003
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EXTENSIONS
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Corrected by G. C. Greubel, Apr 23 2017.
Edited by N. J. A. Sloane, Apr 23 2017
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STATUS
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approved
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