Number of generalized fusenes with n pentagons.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =7a(5) =18a(6) =35a(7) =87a(8) =206a(9) =527a(10) =1337a(11) =3524a(12) =9262a(13) =24772a(14) =66402a(15) =179589a(16) =487435a(17) =1330708a(18) =3645754a(19) =10031143a(20) =27691894a(21) =76708835a(22) =213122892a(23) =593851624a(24) =1659104995a(25) =4646951873a(26) =13046181167a(27) =36708619646a(28) =103505545079a(29) =292430771955