Number of strictly totally positive 3 X 3 matrices having all terms in {1,...,n}.

Terms

a(0) =0a(1) =0a(2) =22a(3) =597a(4) =7178a(5) =43090a(6) =207494a(7) =748801a(8) =2321973a(9) =6267631a(10) =15596170a(11) =34784307a(12) =74017706a(13) =147072570a(14) =277965322a(15) =503711791a(16) =884612799a(17) =1491687919a(18) =2458600175a(19) =3925566799a(20) =6133712065a(21) =9388594434a(22) =14121653942a(23) =20783339478a(24) =30178942357a(25) =43156537147a(26) =60868287839a(27) =84699183224a(28) =116688767652