OFFSET
0,1
COMMENTS
The distinction between different kinds of recursive calls is based on a naive implementation of the Ackermann function in C.
int ack(int m, int n)
{
// Final result
....if (m==0) return n + 1;
.
// Recursive calls of the first kind:
....if (n==0) return ack(m - 1, 1);
.
// Recursive calls of the second kind:
....return ack(m - 1, ack(m, n - 1));
}
LINKS
Index entries for linear recurrences with constant coefficients, signature (8,-21,22,-8).
FORMULA
G.f.: (8*x^2-14*x+9)/((4*x-1)*(2*x-1)*(x-1)^2). - Alois P. Heinz, May 12 2018
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Olivier Gérard, May 11 2018
STATUS
approved