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A069117 Numbers n such that A068589(n) is a perfect square. 0
1, 2, 3, 4, 5, 9, 10, 11, 12, 13, 14, 15, 16, 17, 21, 22, 23, 27, 28, 29, 30, 31, 32, 63, 64, 65, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 105, 106, 107, 108, 109, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 189, 190, 191, 192, 193, 194, 195 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..62.

PROG

(PARI) precision 1000 digits : for(n=1, 300, if(sqrt(denominator(sum(i=1, n, 1/i^3))/denominator(sum(i=1, n, 1/i))) == floor(sqrt(denominator(sum(i=1, n, 1/i^3))/denominator(sum(i=1, n, 1/i)))), print1(n, ", ")))

CROSSREFS

Sequence in context: A052270 A265335 A179223 * A098464 A068586 A068585

Adjacent sequences:  A069114 A069115 A069116 * A069118 A069119 A069120

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Apr 07 2002

STATUS

approved

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Last modified October 27 20:18 EDT 2021. Contains 348290 sequences. (Running on oeis4.)