Number of bargraphs of site-perimeter n.

Terms

a(0) =0a(1) =0a(2) =0a(3) =1a(4) =0a(5) =2a(6) =2a(7) =4a(8) =8a(9) =14a(10) =26a(11) =52a(12) =97a(13) =193a(14) =377a(15) =752a(16) =1500a(17) =3022a(18) =6107a(19) =12429a(20) =25365a(21) =52042a(22) =107090a(23) =221235a(24) =458316a(25) =952439a(26) =1984262a(27) =4144601a(28) =8676232a(29) =18202536