Number of centered 5-valent trees with n nodes.

Terms

a(0) =0a(1) =1a(2) =0a(3) =1a(4) =1a(5) =2a(6) =3a(7) =6a(8) =11a(9) =24a(10) =48a(11) =109a(12) =242a(13) =574a(14) =1346a(15) =3258a(16) =7928a(17) =19664a(18) =49158a(19) =124384a(20) =316791a(21) =813231a(22) =2099326a(23) =5451613a(24) =14226697a(25) =37306971a(26) =98247737a(27) =259779698a(28) =689385447a(29) =1835644498