A365332 - OEIS

A365332

The sum of divisors of the largest square dividing n.

1, 1, 1, 7, 1, 1, 1, 7, 13, 1, 1, 7, 1, 1, 1, 31, 1, 13, 1, 7, 1, 1, 1, 7, 31, 1, 13, 7, 1, 1, 1, 31, 1, 1, 1, 91, 1, 1, 1, 7, 1, 1, 1, 7, 13, 1, 1, 31, 57, 31, 1, 7, 1, 13, 1, 7, 1, 1, 1, 7, 1, 1, 13, 127, 1, 1, 1, 7, 1, 1, 1, 91, 1, 1, 31, 7, 1, 1, 1, 31, 121

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OFFSET

1,4

COMMENTS

All the terms are odd.

The number of these divisors is A365331(n).

The sum of divisors of the square root of the largest square dividing n is A069290(n).

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A000203(A008833(n)).

a(n) = 1 if and only if n is squarefree (A005117).