#include <stdio.h>

unsigned long 
a(int n)
{
    unsigned long ret = 0;

    if( n > 0) {
        ret = a(n-1);
    } else {
        return 2;
    }

    return 2*ret*ret -3*ret + 1;
}

int 
main(void)
{
    int i;

    for(i = 0; i < 10; ++i) {
        printf("a(%d):%lu\n", i, a(i));
    }
    return 0;
}