Number of monocyclic skeletons with n carbon atoms and a ring size of 7.

Terms

a(0) =1a(1) =1a(2) =5a(3) =13a(4) =47a(5) =136a(6) =428a(7) =1252a(8) =3716a(9) =10708a(10) =30823a(11) =87504a(12) =247438a(13) =694588a(14) =1942866a(15) =5411640a(16) =15034045a(17) =41659417a(18) =115231598a(19) =318231047a(20) =877817312a(21) =2419033683a(22) =6661335192a(23) =18332784221a(24) =50432439047a(25) =138692804603a(26) =381332833730