Small-number statistic from the enumeration of domino tilings of a 9-pillow of order n.

Terms

a(0) =1a(1) =2a(2) =5a(3) =13a(4) =34a(5) =89a(6) =89a(7) =193a(8) =185a(9) =410a(10) =482a(11) =1444a(12) =2018a(13) =6362a(14) =8461a(15) =19885a(16) =22861a(17) =51125a(18) =59792a(19) =146749a(20) =195749a(21) =529114a(22) =730465a(23) =1907545a(24) =2350177a(25) =5638489a(26) =6692337a(27) =16167545a(28) =20091490a(29) =51762100