/* * Calculate the integral I_n = \int_0^1 x^n e^(-x) dx * using the (unstable) forward recurrence relation * * I_{n} = n*I_{n-1} - 1/e */ #include <stdio.h> #include <math.h> int main (void) { int i, n = 16; double I; I = 1. - 1./M_E; for (i = 1; i < n; i++) { I = -1./M_E + i*I; printf ("%3d % 24.14f\n", i, I); } return 0; }