affine Fibonacci {N|N>0} returns int Fib {i|0<=i 0 && n==0} : P[d-1,n]; {|n> 0 && n < d} : P[d-1,n-1] + P[d-1,n]; {|d> 0 && n == d} : P[d-1,n-1]; esac; Fib[i] = reduce(+, (d,n->d+n), P[d,n]); .