G.f.: (1-9*x+29*x^2-30*x^3+10*x^4-x^5-(1-6*x+x^2)^(1/2)*(1-6*x+13*x^2-7*x^3+x^4))/(2*x).

A078487

G.f.: (1-9*x+29*x^2-30*x^3+10*x^4-x^5-(1-6*x+x^2)^(1/2)*(1-6*x+13*x^2-7*x^3+x^4))/(2*x).

Terms

    a(0) =0a(1) =1a(2) =2a(3) =6a(4) =23a(5) =100a(6) =464a(7) =2236a(8) =11048a(9) =55588a(10) =283648a(11) =1463868a(12) =7626296a(13) =40049188a(14) =211768752a(15) =1126513788a(16) =6024316488a(17) =32368294756a(18) =174645900768a(19) =945893037948

External references