Number of 2 X 2 matrices with entries in {0,1,...,n} and odd determinant with no entry repeated.

Terms

a(0) =0a(1) =0a(2) =0a(3) =8a(4) =24a(5) =144a(6) =240a(7) =672a(8) =960a(9) =2000a(10) =2640a(11) =4680a(12) =5880a(13) =9408a(14) =11424a(15) =17024a(16) =20160a(17) =28512a(18) =33120a(19) =45000a(20) =51480a(21) =67760a(22) =76560a(23) =98208a(24) =109824a(25) =137904a(26) =152880a(27) =188552a(28) =207480a(29) =252000