The ruler function

gistfile1.c

#include <math.h>
#include <stdio.h>

/* The ruler function corresponds to the number of ones at the end of the 
 * binary representation of numbers. */ 

int main(void) {
  int i;
  for (i = 1; i < 1000; i++) {
    printf("%g ", log2( (i ^ (i-1)) + 1));
    if (i % 32 == 0) {
      printf("\n");
    }
  }
  printf("\n");
  return 0;
}