№15 — #15108

d = []
for a in range(1, 1000):
    if all((6 * x + 1 * y > a) or (x >= 10) or (y >= 14) for x in range(1, 400) for y in range(1, 400)) == 1:
        d.append(a)
d.sort()
print(max(d))