def f(): for n in count(1): pn = pentagonal(n) lower_pentagonals = [pentagonal(i) for i in range(1, n)] for p in lower_pentagonals: if pn - p in Pentagonals and pn + p in Pentagonals: return pn - p
def main(): t_index = 285 p_index = 165 h_index = 143 pentagonal = euler.pentagonal(p_index) hexagonal = euler.hexagonal(h_index) while True: t_index += 1 triangular = euler.triangular(t_index) if triangular > pentagonal: p_index += 1 pentagonal = euler.pentagonal(p_index) if triangular > hexagonal: h_index += 1 hexagonal = euler.hexagonal(h_index) if triangular == pentagonal == hexagonal: break return triangular
def main(): lst = [euler.pentagonal(i) for i in range(100000)] s = set(lst) for k in range(1, 100000): penta_k = lst[k] for j in range(1, k): penta_j = lst[j] if penta_k - penta_j in s: if penta_k + penta_j in s: return penta_k - penta_j return 0
from itertools import count, takewhile from euler import pentagonal, is_pentagonal result = () pentagonals_generated = set() for n in count(1): pentagon_n = pentagonal(n) pentagonals_generated.add(pentagon_n) for pentagon_sub_n in takewhile(lambda p_sub_n: p_sub_n < pentagon_n, pentagonals_generated): pentagon_diff = pentagon_n - pentagon_sub_n if pentagon_diff in pentagonals_generated: pentagon_sum = pentagon_n + pentagon_sub_n if is_pentagonal(pentagon_sum): result = (pentagon_diff, n, pentagon_n, pentagon_sub_n, pentagon_sum) break else: continue break print "D: %d, n: %d, pentagon_n: %d, pentagon_sub_n: %d, pentagon_sumb: %d" % result
from itertools import count from euler import pentagonal, is_pentagonal result = () for n in count(1): pentagon_n = pentagonal(n) for sub_n in xrange(1, n): pentagon_sub_n = pentagonal(sub_n) pentagon_diff = pentagon_n - pentagon_sub_n if is_pentagonal(pentagon_diff): pentagon_sum = pentagon_n + pentagon_sub_n if is_pentagonal(pentagon_sum): result = (pentagon_diff, n, sub_n, pentagon_n, pentagon_sub_n, pentagon_sum) break else: continue break print "D: %d, n: %d, sub_n: %d, pentagon_n: %d, pentagon_sub_n: %d, pentagon_sumb: %d" % result