

A257309


Perfect hyper4 powers: a^^b, where b <> 1.


4



0, 1, 4, 16, 27, 256, 3125, 46656, 65536, 823543, 16777216, 387420489, 10000000000, 285311670611, 7625597484987, 8916100448256, 302875106592253, 11112006825558016, 437893890380859375, 18446744073709551616, 827240261886336764177, 39346408075296537575424, 1978419655660313589123979, 104857600000000000000000000
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OFFSET

1,3


COMMENTS

a^^b is the right associative power tower a^a^...^a^a of height b. a^^1= 0 and a^^0 = 1. We exclude b=1 because otherwise all natural numbers would be in the sequence.


LINKS



EXAMPLE

Numbers written as power towers include:
5^^2 = 5^5 = 3125;
3^^3 = 3^3^3 = 3^27 = 7625597484987;
2^^4 = 2^2^2^2 = 2^2^4 = 2^16 = 65536;
0^^5 = 0^0^0^0^0 = 0^0^0^1 = 0^0^0 = 0^1 = 0;


CROSSREFS



KEYWORD

nonn


AUTHOR



STATUS

approved



