Card-matching numbers (Dinner-Diner matching numbers).

Terms

a(0) =1a(1) =44a(2) =45a(3) =20a(4) =10a(5) =0a(6) =1a(7) =13756a(8) =30480a(9) =32365a(10) =21760a(11) =10300a(12) =3568a(13) =970a(14) =160a(15) =40a(16) =0a(17) =1a(18) =6699824a(19) =23123880a(20) =38358540a(21) =40563765a(22) =30573900a(23) =17399178a(24) =7723640a(25) =2729295a(26) =776520a(27) =180100a(28) =33372a(29) =5355