G.f. satisfies: A(x) = 1 + x*A(x)^2 + 2*x^2*(A(x)^2 - A(x)); equals the base sequence of pendular trinomial triangle A122445.
A122446
G.f. satisfies: A(x) = 1 + x*A(x)^2 + 2*x^2*(A(x)^2 - A(x)); equals the base sequence of pendular trinomial triangle A122445.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =7a(4) =24a(5) =88a(6) =336a(7) =1321a(8) =5316a(9) =21788a(10) =90640a(11) =381750a(12) =1624592a(13) =6975136a(14) =30177056a(15) =131428917a(16) =575765820a(17) =2535433668a(18) =11216757104a(19) =49829385786a(20) =222193501760a(21) =994153952528
External references
- oeis: A122446