Numbers of isomers of unbranched a-4-catapolypentagons - see Brunvoll reference for precise definition.

A121136

Numbers of isomers of unbranched a-4-catapolypentagons - see Brunvoll reference for precise definition.

Terms

    a(0) =1a(1) =3a(2) =13a(3) =45a(4) =164a(5) =527a(6) =1652a(7) =4876a(8) =14000a(9) =38800a(10) =105112a(11) =278104a(12) =722736a(13) =1846320a(14) =4650368a(15) =11560320a(16) =28413312a(17) =69111168a(18) =166551680a(19) =397975680a(20) =943672576a(21) =2221821184a(22) =5197313024a(23) =12084884480a(24) =27944656896a(25) =64286203904a(26) =147182565376

External references