OFFSET
0,2
COMMENTS
Next term is 128 * 8^128 = 2^391, which has 118 digits.
This function is a particular instance of the fast-iteration hierarchy function F[k]_n(x). This sequence is also a(n) = F[n]_3(2). See A275000 for details and definitions and formulae.
a(n) is an even function.
FORMULA
a(n) = f_3(2), with f_0(x) = x+n, f_k+1(x) = (f_k)^x(x).
a(n) = a(-n) because 2*h^(2*h^2 + 2) = 2*(-h)^(2*(-h)^2 + 2).
MATHEMATICA
Table[2 n^(2 n^2 + 2), {n, 0, 7}] (* Michael De Vlieger, Nov 30 2016 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Natan Arie Consigli, Nov 09 2016
STATUS
approved