A336965 a(n) is the product of the distinct prime numbers appearing in the prime tower factorization of n.

1, 2, 3, 2, 5, 6, 7, 6, 6, 10, 11, 6, 13, 14, 15, 2, 17, 6, 19, 10, 21, 22, 23, 6, 10, 26, 3, 14, 29, 30, 31, 10, 33, 34, 35, 6, 37, 38, 39, 30, 41, 42, 43, 22, 30, 46, 47, 6, 14, 10, 51, 26, 53, 6, 55, 42, 57, 58, 59, 30, 61, 62, 42, 6, 65, 66, 67, 34, 69, 70

Offset

1,2

Comments

The prime tower factorization of a number is defined in A182318.

For any n > 0, a(n) is the product of the terms in n-th row of A336964.

Links

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

Example

A001221(a(n)) = A115588(n) for any n > 1.
a(n) = A007947(A279513(n)).
a(n) = n iff n is squarefree (A005117).

Prog

(PARI) a(n) = { my (f=factor(n), v=vecprod(f[, 1]~)); for (k=1, #f~, v=lcm(v, a(f[k, 2]))); v }

Crossrefs

Cf. A001221, A005117, A007947, A115588, A182318, A336964.

Sequence in context: A186646 A309108 A308056 * A293303 A333569 A110500

Adjacent sequences: A336962 A336963 A336964 * A336966 A336967 A336968

Keyword

nonn

Author

Rémy Sigrist, Aug 09 2020

Status

approved