A381538 Numbers of the form m^(m^k).

1, 4, 16, 27, 256, 3125, 19683, 46656, 65536, 823543, 16777216, 387420489, 4294967296, 10000000000, 285311670611, 7625597484987, 8916100448256, 302875106592253, 11112006825558016, 298023223876953125, 437893890380859375, 18446744073709551616

Offset: 1

Author

Charles L. Hohn, Feb 26 2025

Keywords

• nonn

Examples

			27 = 3^(3^1) -> a(4).
256 = 2^(2^3) = 4^(4^1) -> a(5).
		

Crossrefs

Subsequence of A001597; supersequence of A000312 (apart from initial term), A097374, and A257309 (apart from initial term).

Subset of A380760 for a(n)>=16, and of A067688 for prime m.

Programs

PARI

upto(limit)=my(L=List([1])); for(m=2, oo, my(t=logint(limit,m)); if(tAndrew Howroyd, Feb 26 2025