

A188049


Numbers k such that k^k1 and k^k+1 are both not squarefree.


0



17, 18, 19, 40, 49, 51, 53, 55, 69, 82, 89, 91, 97, 99, 117, 118
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OFFSET

1,1


LINKS



EXAMPLE

17 is a term since 17^171 = 2^4*10949*1749233*2699538733 and 17^17+1 = 2*3^2*45957792327018709121.


MATHEMATICA

Select[Range@41, !(SquareFreeQ[#^#1]SquareFreeQ[#^#+1])&]


PROG

(PARI) isok(k) = ! issquarefree(k^k1) && ! issquarefree(k^k+1); \\ Michel Marcus, Feb 22 2021


CROSSREFS



KEYWORD

nonn,hard,more


AUTHOR



EXTENSIONS



STATUS

approved



