A396067 Product of odd divisors of n that are <= sqrt(n).

1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 3, 1, 1, 3, 1, 1, 3, 1, 1, 3, 1, 1, 3, 5, 1, 3, 1, 1, 15, 1, 1, 3, 1, 5, 3, 1, 1, 3, 5, 1, 3, 1, 1, 15, 1, 1, 3, 7, 5, 3, 1, 1, 3, 5, 7, 3, 1, 1, 15, 1, 1, 21, 1, 5, 3, 1, 1, 3, 35, 1, 3, 1, 1, 15, 1, 7, 3, 1, 5, 27, 1, 1, 21, 5

Offset

1,9

Links

Table of n, a(n) for n=1..85.

Mathematica

a[n_] := Times @@ Select[Divisors[n], OddQ[#] && # <= Sqrt[n] &]; Array[a, 85]

Prog

(PARI) a(n) = vecprod(select(x->(x<=sqrt(n) && ((x%2)==1)), divisors(n))); \\ Michel Marcus, May 15 2026

Crossrefs

Cf. A007955, A069289, A072499, A136655, A382486, A396068.

Sequence in context: A132951 A366520 A366519 * A353517 A353487 A356308

Adjacent sequences: A396064 A396065 A396066 * A396068 A396069 A396070

Keyword

nonn,easy

Author

Ilya Gutkovskiy, May 15 2026

Status

approved