Number of (undirected) Hamiltonian paths in the n-dipyramidal graph.

Terms

a(0) =36a(1) =120a(2) =310a(3) =660a(4) =1218a(5) =2032a(6) =3150a(7) =4620a(8) =6490a(9) =8808a(10) =11622a(11) =14980a(12) =18930a(13) =23520a(14) =28798a(15) =34812a(16) =41610a(17) =49240a(18) =57750a(19) =67188a(20) =77602a(21) =89040a(22) =101550a(23) =115180a(24) =129978a(25) =145992a(26) =163270a(27) =181860a(28) =201810a(29) =223168