A133454 Chain of 6 highly composite numbers generated when subject to the recurrence relation tau(a(n+1)) = a(n), with a(0)=3, where tau(n) is the number-of-divisors function A000005(n).

4, 6, 12, 60, 5040, 293318625600

Offset: 1

Author

Lekraj Beedassy, Dec 22 2007

Keywords

• fini
• full
• nonn

Comments

We omit the seed a(0) from the sequence and keep the offset at 1, because 3 is not highly composite. - R. J. Mathar, Jun 20 2021

Examples

			Since 4 is the HCN with 3 divisors, we have tau(4) = 3 and therefore a(1)=4; the HCN with 4 divisors is 6, so that tau(6) = 4 and hence a(2)=6; the HCN with 6 divisors is 12 so that tau(12) = 6, implying a(3)=12, ...
		

Crossrefs

Cf. A002182.

A finite subsequence of A009287.