A363098 Primitive terms of A363063.

2, 12, 720, 864, 4320, 21600, 62208, 151200, 311040, 1555200, 7776000, 10886400, 54432000, 381024000, 4191264000, 160030080000, 251475840000, 1760330880000, 11522165760000, 19363639680000, 126743823360000, 251727315840000, 403275801600000, 829595934720000

Offset

1,1

Comments

Numbers k > 1 in A363063 such that there are no i, j > 1 in A363063 with k = i*j.

Factorization into primitive terms of A363063 is not unique. The first counterexample is 1728 = 864 * 2 = 12^3.

For every odd prime p there are infinitely many terms whose greatest prime factor is p. Reading along the sequence, we see a term with a new greatest prime factor if and only if it is in A347284.

Links

Pontus von Brömssen, Table of n, a(n) for n = 1..10000

Example

4 is in A363063, but is not a term here, because 2 is in A363063 and 2 * 2 = 4.
720 is the first term of A363063 that is divisible by 5, from which we deduce 720 is not a product of nonunit terms of A363063. So 720 is a term here.

Crossrefs

Cf. A347284, A363063.

Sequence in context: A216335 A173104 A141770 * A230265 A060055 A363234

Adjacent sequences: A363095 A363096 A363097 * A363099 A363100 A363101

Keyword

nonn

Author

Pontus von Brömssen and Peter Munn, May 19 2023

Status

approved