doubt in the chapter of multinomial theorem

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the question stated to find the sum of all coefficients divisible by 37 in the expansion of $ (2x+y+z)^{37} $

I proceeded by writing out

$ (2x+y+z)^{37} $ = $ \sum_{0 \le p,q,r \le 37} $ (${ (37!) 2^p \over (p! (q!) (r!)}$ ) $ x^p y^q z^ r $ where p + q + r = 37.

but got stuck at this point