a(n) = binomial(n+2,3)*4^3.

Terms

a(0) =64a(1) =256a(2) =640a(3) =1280a(4) =2240a(5) =3584a(6) =5376a(7) =7680a(8) =10560a(9) =14080a(10) =18304a(11) =23296a(12) =29120a(13) =35840a(14) =43520a(15) =52224a(16) =62016a(17) =72960a(18) =85120a(19) =98560a(20) =113344a(21) =129536a(22) =147200a(23) =166400a(24) =187200a(25) =209664a(26) =233856a(27) =259840a(28) =287680a(29) =317440