A156329 Smallest tetrahedral number with n distinct prime factors.

4, 10, 84, 1140, 7140, 125580, 2929290, 161226780, 2875585020, 32451432090, 9117204216120, 173092525291140, 12728365882372140, 6235727798083743960, 843456728066008506450, 68313970807402942762140, 7219596660397839675355860, 211677272048242059920400540

Offset: 1

Author

Donovan Johnson, Feb 08 2009

Keywords

• nonn

Examples

			a(9) = 2875585020 = 2^2*3*5*7*11*17*19*41*47. 2875585020 is the smallest tetrahedral number with 9 distinct prime factors.
		

Links

• Donovan Johnson, Table of n, a(n) for n = 1..22
• Eric Weisstein's World of Mathematics, Tetrahedral Numbers.

Crossrefs

Cf. A000292.

Extensions

Edited by Donovan Johnson, Nov 24 2010

a(18) added (from b-file) by Jon E. Schoenfield, Dec 17 2022