OFFSET
0,4
COMMENTS
n^^k is defined the left-associative 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^(k-1)).
More terms on Munafo website.
LINKS
Robert Munafo, Hyper4 Iterated Exponential Function.
EXAMPLE
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,...
MATHEMATICA
T[n_, k_] := If[n == 0, Boole[k != 0], n^(n^k)]; Table[T[k, n - k], {n, 0, 7}, {k, n, 0, -1}] // Flatten (* Amiram Eldar, Oct 29 2021 *)
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Robert Munafo, Jan 21 2010
STATUS
approved