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

Terms

a(0) =1a(1) =61a(2) =797a(3) =6490a(4) =32744a(5) =146441a(6) =492277a(7) =1521123a(8) =4105795a(9) =10194558a(10) =22922408a(11) =49594408a(12) =98935110a(13) =190221734a(14) =350417949a(15) =621178227a(16) =1058404994a(17) =1764873413a(18) =2845696865a(19) =4506618651a(20) =6966717779a(21) =10552756376a(22) =15670141644a(23) =22984055065a(24) =33094853060a(25) =47016605050a(26) =65934960254a(27) =91414399149