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A348581

a(n) is the least factor among all the products A307720(k) * A307720(k+1) equal to n.

1, 1, 1, 2, 1, 2, 1, 2, 3, 2, 1, 3, 1, 2, 3, 2, 1, 3, 1, 4, 3, 2, 1, 3, 5, 2, 3, 4, 1, 5, 1, 4, 3, 2, 5, 4, 1, 2, 3, 5, 1, 6, 1, 4, 5, 2, 1, 6, 7, 5, 3, 4, 1, 6, 5, 7, 3, 2, 1, 6, 1, 2, 7, 8, 5, 6, 1, 4, 3, 7, 1, 8, 1, 2, 5, 4, 7, 6, 1, 8, 9, 2, 1, 7, 5, 2, 3

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OFFSET

1,4

COMMENTS

We know there are n ways to get n as a product of terms A307720(k)*A307720(k+1) for various k's. Look at these 2*n numbers from A307720. Then a(n) is the smallest of them.

LINKS

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Rémy Sigrist, C program for A348581

FORMULA

a(p) = 1 for any prime number p.

a(n) * A348582(n) = n.

EXAMPLE

For n = 6:

- we have the following products equal to 6:

A307720(7) * A307720(8) = 3 * 2 = 6

A307720(12) * A307720(13) = 2 * 3 = 6

A307720(13) * A307720(14) = 3 * 2 = 6