OFFSET
1,2
COMMENTS
a[n]b is the square bracket notation for hyperoperation. See A054871 for more info.
EXAMPLE
a(1) = 1;
a(2) = 1+2 = 3;
a(3) = 1+2*3 = 7;
a(4) = 1+2*3^4 = 163;
a(5) = 1+2*3^4^^5 which is too big to be included.
CROSSREFS
KEYWORD
nonn
AUTHOR
Natan Arie Consigli, Nov 29 2015
STATUS
approved