Number of left-labeled (3,n)-bipartite graphs.

Terms

a(0) =1a(1) =8a(2) =25a(3) =60a(4) =129a(5) =256a(6) =484a(7) =872a(8) =1512a(9) =2532a(10) =4110a(11) =6484a(12) =9975a(13) =14992a(14) =22065a(15) =31860a(16) =45207a(17) =63126a(18) =86868a(19) =117934a(20) =158130a(21) =209600a(22) =274874a(23) =356916a(24) =459189a(25) =585694a(26) =741053a(27) =930566a(28) =1160285a(29) =1437090