G.f.: (1 - 4*x - sqrt(16*x^2 - 12*x + 1))/(2*x).
A082301
G.f.: (1 - 4*x - sqrt(16*x^2 - 12*x + 1))/(2*x).
Terms
- a(0) =1a(1) =5a(2) =30a(3) =205a(4) =1530a(5) =12130a(6) =100380a(7) =857405a(8) =7503330a(9) =66931030a(10) =606337380a(11) =5563370130a(12) =51594699780a(13) =482860844580
External references
- oeis: A082301