double countdivisors(BigInt n, BigInt k){
if (k == 0) return 1;
if (k == 1) return n - 1;
BigInt t = 0;
for (BigInt i = 2; i <= n; i++) t += countdivisors( n / i, k - 1 );
return t;
}
BigInt countprimes1( BigInt n){
double t = 0.0;
for (BigInt j = 1; j < log((double)n) / log(2.0); j++)
for (BigInt k = 1; k < log( pow( n, 1.0 / j ) ) / log(2.0); k++)
t += pow( -1.0, (double)k+1 ) * countdivisors(pow( n, 1.0 / j ), k)
/ k / j * mu[j];
return (t+.1);
}
int main(int argc, char **argv) {
long long i = 0, triangle = 0, count = -1;
while (count < 500) {
count = countdivisors(triangle += ++i);
if (count > 200)
printf("i: %lld\ttriangle: %lld\tcount: %lld\n", i, triangle, count);
}
printf("number: %lld - count: %lld\n", triangle, count);
return 0;
}
