Number of 2 X 2 matrices having all terms in {1,...,n} and determinant >n.

Terms

a(0) =0a(1) =1a(2) =12a(3) =53a(4) =158a(5) =361a(6) =740a(7) =1326a(8) =2235a(9) =3524a(10) =5361a(11) =7711a(12) =10926a(13) =14941a(14) =20011a(15) =26217a(16) =33964a(17) =43007a(18) =54094a(19) =66834a(20) =81956a(21) =99455a(22) =119872a(23) =142543a(24) =169036a(25) =198791a(26) =232419a(27) =269781a(28) =312224a(29) =358359