Number of closed walks of length n in a kite graph (K4 with one edge deleted).

Terms

a(0) =4a(1) =0a(2) =10a(3) =12a(4) =50a(5) =100a(6) =298a(7) =700a(8) =1890a(9) =4692a(10) =12250a(11) =31020a(12) =80018a(13) =204100a(14) =524170a(15) =1340572a(16) =3437250a(17) =8799540a(18) =22548538a(19) =57746700a(20) =147940850a(21) =378927652a(22) =970691050a(23) =2486401660a(24) =6369165858a(25) =16314772500a(26) =41791435930a(27) =107050525932a(28) =274216269650a(29) =702418373380