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A336965 a(n) is the product of the distinct prime numbers appearing in the prime tower factorization of n. 2
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified December 5 15:27 EST 2022. Contains 358588 sequences. (Running on oeis4.)