G.f. A(x) satisfies: A(x) = (1 + x * A(x)^2) / (1 - x + 2 * x^2).
A346505
G.f. A(x) satisfies: A(x) = (1 + x * A(x)^2) / (1 - x + 2 * x^2).
Terms
- a(0) =1a(1) =2a(2) =4a(3) =12a(4) =44a(5) =172a(6) =700a(7) =2940a(8) =12652a(9) =55500a(10) =247260a(11) =1115740a(12) =5088908a(13) =23423020a(14) =108659324a(15) =507520316a(16) =2384733868a(17) =11264884876a(18) =53464215580a(19) =254822253852
External references
- oeis: A346505