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A069186
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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).
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1
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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
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OFFSET
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1,2
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COMMENTS
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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
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LINKS
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MAPLE
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select(numtheory:-issqrfree, [1, seq(seq(b^2+j, j=-2..-1), b=2..100)]); # Robert Israel, Apr 11 2019
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PROG
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(PARI) isok(n) = core(n) == sqrtint(n); \\ Michel Marcus, Apr 12 2019
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CROSSREFS
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KEYWORD
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easy,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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