OFFSET
1,2
LINKS
Michel Marcus, Table of n, a(n) for n = 1..10000
MATHEMATICA
Table[Length[Select[Range[n], #/Last[Select[Divisors[#], SquareFreeQ]] == n/Last[Select[Divisors[n], SquareFreeQ]] &]], {n, 1, 80}]
PROG
(PARI) f(n) = n/factorback(factor(n)[, 1]); \\ A003557
a(n) = my(x=f(n)); sum(j=1, n, f(j) == x); \\ Michel Marcus, Sep 20 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Sep 19 2022
STATUS
approved