Expansion of (1+x^4*C^2)*C^2, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.
A071747
Expansion of (1+x^4*C^2)*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) =136a(6) =443a(7) =1478a(8) =5027a(9) =17368a(10) =60788a(11) =215084a(12) =768094a(13) =2764880a(14) =10021721a(15) =36546310a(16) =133990755a(17) =493606680a(18) =1826192640a(19) =6782469540a(20) =25278252810a(21) =94512157680a(22) =354397639830
External references
- oeis: A071747