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A122842
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Square roots of the odd indexed terms of A038547.
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4
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1, 3, 9, 27, 15, 243, 729, 45, 6561, 19683, 135, 177147, 225, 105, 4782969, 14348907, 1215, 675, 387420489, 3645, 3486784401, 10460353203, 315, 94143178827, 3375, 32805, 2541865828329, 6075, 98415, 68630377364883
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OFFSET
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1,2
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COMMENTS
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A038547(n) is the least number with exactly n odd divisors. For odd n these are perfect squares.
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LINKS
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FORMULA
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a(n) = sqrt(A119265(2*n-1, 2*n-1)).
a(n) = 3^(n-1) for n = (p+1)/2, where p is an odd prime.
a(3*n+2) = 5*3^n for n = (p-1)/2, where p is an odd prime.
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EXAMPLE
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a(5) = 15 because A038547(9) = 225.
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MATHEMATICA
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(* Function a038547[ ] is defined in A038547 *)
a122842[n_]:=Sqrt[a038547[2n-1]]
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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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