Upper triangular region of the table A073345.

Terms

a(0) =1a(1) =0a(2) =1a(3) =0a(4) =0a(5) =2a(6) =0a(7) =0a(8) =1a(9) =4a(10) =0a(11) =0a(12) =0a(13) =6a(14) =8a(15) =0a(16) =0a(17) =0a(18) =6a(19) =20a(20) =16a(21) =0a(22) =0a(23) =0a(24) =4a(25) =40a(26) =56a(27) =32a(28) =0a(29) =0