Number of (undirected) cycles in the n-flower graph.

Terms

a(0) =4a(1) =15a(2) =100a(3) =369a(4) =1444a(5) =5181a(6) =18820a(7) =66885a(8) =238852a(9) =847899a(10) =3019108a(11) =10751055a(12) =38407204a(13) =137542911a(14) =494292484a(15) =1782149517a(16) =6448032004a(17) =23406996777a(18) =85243901284a(19) =311368569873