

A171881


Square array, read by antidiagonals, where T(n,k)=n^^k for n>=0, k>=1.


1



0, 1, 1, 2, 1, 1, 3, 4, 1, 1, 4, 27, 16, 1, 1, 5, 256, 19683, 256, 1, 1, 6, 3125, 4294967296, 7625597484987, 65536, 1, 1, 7, 46656, 298023223876953125, 340282366920938463463374607431768211456
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OFFSET

0,4


COMMENTS

n^^k is defined the leftassociative way: n^^2=n^n, n^^3=(n^n)^n=n^(n^2), n^^4=((n^n)^n)^n=n^(n^3), and in general n^^k=n^(n^(k1)).
More terms on Munafo website.
Array begins:
0,1,1,1,1,1,...
1,1,1,1,1,1,...
2,4,16,256,65536,...
3,27,19683,...
4,256,4294967296,...
5,3125,...
6,46656,...


LINKS

Table of n, a(n) for n=0..31.
R. Munafo, Hyper4 Iterated Exponential Function


CROSSREFS

Cf. A171882.
Sequence in context: A104495 A093541 A336187 * A321877 A320251 A210341
Adjacent sequences: A171878 A171879 A171880 * A171882 A171883 A171884


KEYWORD

nonn,tabl


AUTHOR

Robert Munafo, Jan 21 2010


STATUS

approved



