a(n) = Sum_{k=0..2*n} (-1)^k * binomial(12*n,6*k).A232732a(n) = Sum_{k=0..2*n} (-1)^k * binomial(12*n,6*k).Terms a(0) =-922a(1) =2434966a(2) =-6575675482External referencesoeis: A232732