Expansion of (1+x^4*C^4)*C^2, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.
A071755
Expansion of (1+x^4*C^4)*C^2, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.
Terms
- a(0) =1a(1) =2a(2) =5a(3) =14a(4) =43a(5) =138a(6) =456a(7) =1540a(8) =5291a(9) =18434a(10) =64974a(11) =231268a(12) =830110a(13) =3001316a(14) =10920630a(15) =39959280a(16) =146943435a(17) =542771250a(18) =2012905950a(19) =7492104180a(20) =27977841930a(21) =104792420460a(22) =393587773800
External references
- oeis: A071755