A161845 a(n) = A002808(n)^A141468(n).

1, 6, 4096, 531441, 100000000, 5159780352, 289254654976, 129746337890625, 72057594037927936, 6746640616477458432, 655360000000000000000, 630880792396715529789561, 705429498686404044207947776, 96479729228174488169059713024

Offset: 1

Author

Juri-Stepan Gerasimov, Jun 20 2009

Keywords

• nonn

Comments

The n-th composite raised to the power m, where m = n-th nonprime.

Examples

			a(1) = 4^0 = 1;
a(2) = 6^1 = 6;
a(3) = 8^4 = 4096;
a(4) = 9^6 = 531441;
a(5) = 10^8 = 100000000;
a(6) = 12^9 = 5159780352.
		

Crossrefs

Cf. A002808, A141468.

Programs

Maple

A002808 := proc(n) option remember; local a; if n = 1 then 4; else for a from procname(n-1)+1 do if not isprime(a) then RETURN(a) : fi; od: fi; end:
A141468 := proc(n) if n >= 3 then A002808(n-2) ; else n-1 ; fi; end:
A161845 := proc(n) A002808(n)^A141468(n) ; end:
seq(A161845(n),n=1..20) ; # R. J. Mathar, Jun 23 2009

Extensions

a(4) corrected and extended by R. J. Mathar, Jun 23 2009

Edited by Jon E. Schoenfield, Feb 23 2019