Square array read by antidiagonals: A(m,n) is the number of 2m-by-2n fers-wazir tours.

Terms

a(0) =2a(1) =1a(2) =1a(3) =1a(4) =2a(5) =1a(6) =1a(7) =4a(8) =4a(9) =1a(10) =1a(11) =9a(12) =22a(13) =9a(14) =1a(15) =1a(16) =23a(17) =124a(18) =124a(19) =23a(20) =1a(21) =1a(22) =62a(23) =818a(24) =1620a(25) =818a(26) =62a(27) =1a(28) =1a(29) =170