The largest n N such that 3n divides 50 ! is :
(1) 22
Exponent of the prime 3 in 50! (Legendre's formula):
n = [ 503 ] + [ 509 ] + [ 5027 ] + [ 5081 ]
= 16 + 5 + 1 + 0 = 22
Answer: (1)
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