Square array in A071223 read by antidiagonals.

Terms

a(0) =2a(1) =2a(2) =2a(3) =2a(4) =6a(5) =2a(6) =2a(7) =12a(8) =6a(9) =2a(10) =2a(11) =20a(12) =24a(13) =6a(14) =2a(15) =2a(16) =30a(17) =72a(18) =24a(19) =6a(20) =2a(21) =2a(22) =42a(23) =172a(24) =120a(25) =24a(26) =6a(27) =2a(28) =2a(29) =56