A287621 a(n) = least k such that A287620(k) = n.

1, 2, 3, 18, 5, 6, 7, 450, 24, 10, 11, 150, 13, 14, 15, 22050, 17, 192, 19, 90, 21, 22, 23, 7350, 160, 26, 3000, 126, 29, 30, 31, 2668050, 33, 34, 35, 4800, 37, 38, 39, 4410, 41, 42, 43, 198, 120, 46, 47, 705600, 896, 1440, 51, 234, 53, 24000, 55, 3150, 57, 58

Offset

1,2

Comments

a(n) >= n.

a(n) = n iff n is squarefree (A005117).

If n = p_1 * ... * p_k where p_1, ..., p_k are prime, then a(n) <= prime(1)^p_1 * ... * prime(k)^p_k.

Links

Table of n, a(n) for n=1..58.

Rémy Sigrist, Illustration of the first terms

Example

See illustrations of the first terms in Links section.

Crossrefs

Cf. A005117, A287620.

Sequence in context: A118702 A073524 A130226 * A348279 A344530 A328624

Adjacent sequences: A287618 A287619 A287620 * A287622 A287623 A287624

Keyword

nonn

Author

Rémy Sigrist, May 28 2017

Status

approved