If − 12a2b2n − 1 is a quintic monomial, then the value of n is______ .

If − 12a2b2n − 1 is a quintic monomial, then the value of n is______ .

Because − 12a2b2n − 1 is a quintic monomial, so 2 + 2N-1 = 5, the solution is n = 2, so the answer is 2