Number of 2 X 2 matrices with all elements in {0,1,...,n} and positive odd determinant.

Terms

a(0) =0a(1) =3a(2) =8a(3) =48a(4) =84a(5) =243a(6) =360a(7) =768a(8) =1040a(9) =1875a(10) =2400a(11) =3888a(12) =4788a(13) =7203a(14) =8624a(15) =12288a(16) =14400a(17) =19683a(18) =22680a(19) =30000a(20) =34100a(21) =43923a(22) =49368a(23) =62208a(24) =69264a(25) =85683a(26) =94640a(27) =115248a(28) =126420a(29) =151875