def coprime_method(n, cache={}):
# n is the index of the triangular numbers
triangle_value = triangle_closed_form(n)
try:
primes_n = cache[n]
except KeyError:
primes_n = primes(n)
primes_n_1 = primes(n+1)
cache[n+1] = primes_n_1
primes_t_n = primes_n + primes_n_1
try:
primes_t_n.remove(2)
except ValueError:
pass
cache[triangle_value] = primes_t_n
return triangle_value, find_combos(primes_t_n), cache
def num_divisors_of_n(n): return find_combos(primes(n))
