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A069186
Numbers n such that core(n)=floor(sqrt(n)), where core(x)=A007913(x) is the squarefree part of x and floor(sqrt(x))=A000196(x).
1
1, 8, 12, 63, 224, 240, 575, 1224, 1260, 2303, 3968, 6399, 14399, 20448, 20592, 28223, 38024, 38220, 50175, 65024, 65280, 82943, 104328, 104652, 129599, 159200, 159600, 193599, 233288, 233772, 278783, 330624, 389375, 455624
OFFSET
1,2
COMMENTS
Apart from 1, numbers of the form x*y^2 for y >= 2, where x is squarefree and is either y^2-2 or y^2-1. - Robert Israel, Apr 11 2019
LINKS
MAPLE
select(numtheory:-issqrfree, [1, seq(seq(b^2+j, j=-2..-1), b=2..100)]); # Robert Israel, Apr 11 2019
PROG
(PARI) isok(n) = core(n) == sqrtint(n); \\ Michel Marcus, Apr 12 2019
CROSSREFS
Sequence in context: A298901 A368125 A305236 * A166625 A370651 A038290
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, Apr 14 2002
EXTENSIONS
Name edited by Robert Israel, Apr 12 2019
STATUS
approved