A366521 Largest squarefree divisor of n which is <= sqrt(n).

1, 1, 1, 2, 1, 2, 1, 2, 3, 2, 1, 3, 1, 2, 3, 2, 1, 3, 1, 2, 3, 2, 1, 3, 5, 2, 3, 2, 1, 5, 1, 2, 3, 2, 5, 6, 1, 2, 3, 5, 1, 6, 1, 2, 5, 2, 1, 6, 7, 5, 3, 2, 1, 6, 5, 7, 3, 2, 1, 6, 1, 2, 7, 2, 5, 6, 1, 2, 3, 7, 1, 6, 1, 2, 5, 2, 7, 6, 1, 5, 3, 2, 1, 7, 5, 2, 3, 2, 1, 6, 7, 2, 3, 2, 5, 6, 1, 7, 3, 10

Offset

1,4

Links

Andrew Howroyd, Table of n, a(n) for n = 1..10000

Mathematica

Table[Last[Select[Divisors[n], # <= Sqrt[n] && SquareFreeQ[#] &]], {n, 100}]

Prog

(PARI) a(n) = {my(m=1); fordiv(n, d, if(d^2 <= n && issquarefree(d), m=max(m, d))); m} \\ Andrew Howroyd, Oct 11 2023

Crossrefs

Cf. A007947, A033676, A089384, A366522.

Sequence in context: A072203 A345266 A217581 * A348581 A124044 A059981

Adjacent sequences: A366518 A366519 A366520 * A366522 A366523 A366524

Keyword

nonn

Author

Ilya Gutkovskiy, Oct 11 2023

Status

approved