int p (int n, int m)
{
    if (n == m)
        return 1 + p(n, m - 1);
    if (m == 0 || n < 0)
        return 0;
    if (n == 0 || m == 1)
        return 1;

    return p(n, m - 1) + p(n - m, m);

}

p(n, m) - p(n, m - 1) = p(n-m, m)          (1)

/ 0 (k>n)
p(k,n)={  1 (k=n)
         p(k+1,n)+p(k,n-k) (k<n)

#include <stdio.h>

/* 406 is the largest n for which p(n) fits in 64 bits */
#define MAX 406
long long int pArray[MAX][MAX];

/* Emulate array starting at 1: */
#define p(k,n) pArray[k-1][n-1]

int main(int argc, char **argv) {

 int n, k;

 for (n = 1; n < MAX; n++) {
  for (k = n; k > 0; k--) {
   if (k > n) {
    p(k, n) = 0;
   }
   else if (k == n) {
    p(k, n) = 1;
   }
   else {
    p(k, n) = p(k, n-k)+p(k+1, n);
   }
  }
 }

 for (n = 1; n < MAX; n++) {
  printf("p(%d)=%lldn", n, p(1,n));
 }

}