Square array read by ascending antidiagonals: A(n, k) = 3^n*Pochhammer(k/3, n).

Terms

a(0) =1a(1) =0a(2) =1a(3) =0a(4) =1a(5) =1a(6) =0a(7) =4a(8) =2a(9) =1a(10) =0a(11) =28a(12) =10a(13) =3a(14) =1a(15) =0a(16) =280a(17) =80a(18) =18a(19) =4a(20) =1a(21) =0a(22) =3640a(23) =880a(24) =162a(25) =28a(26) =5a(27) =1a(28) =0a(29) =58240