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1,2
Table of n, a(n) for n=1..65.
{n: A007407(n) in A000290} . - R. J. Mathar, Oct 03 2014
Select[Range[300], IntegerQ[Sqrt[Denominator[Sum[1/k^2, {k, #}]]]]&] (* Harvey P. Dale, Mar 28 2012 *)
Cf. A007407, A073527.
Sequence in context: A242415 A242420 A242419 * A032992 A190298 A069118
Adjacent sequences: A073523 A073524 A073525 * A073527 A073528 A073529
nonn,easy
N. J. A. Sloane, Aug 30 2002
More terms from Matthew Conroy, Sep 09 2002
approved