Numbers of polypentagons with one internal vertex (see Cyvin et al. for precise definition).

Terms

a(0) =0a(1) =0a(2) =1a(3) =4a(4) =10a(5) =27a(6) =67a(7) =166a(8) =396a(9) =934a(10) =2168a(11) =4984a(12) =11332a(13) =25584a(14) =57312a(15) =127624a(16) =282560a(17) =622528a(18) =1365200a(19) =2981760a(20) =6487808a(21) =14068128a(22) =30408192a(23) =65535488a(24) =140857664a(25) =301988864a(26) =645920768a(27) =1378525824a(28) =2936008704a(29) =6241120256