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

A121135

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

Terms

    a(0) =1a(1) =2a(2) =8a(3) =22a(4) =74a(5) =208a(6) =598a(7) =1600a(8) =4248a(9) =10880a(10) =27512a(11) =68096a(12) =166528a(13) =401408a(14) =957728a(15) =2260992a(16) =5292672a(17) =12288000a(18) =28329344a(19) =64880640a(20) =147721216a(21) =334495744a(22) =753670656a(23) =1690304512a(24) =3774887936a(25) =8396996608a(26) =18610157568a(27) =41104179200

External references