A Chebyshev transform of the Catalan numbers.

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =9a(5) =25a(6) =73a(7) =223a(8) =697a(9) =2217a(10) =7161a(11) =23427a(12) =77457a(13) =258417a(14) =868881a(15) =2941311a(16) =10016241a(17) =34289041a(18) =117935473a(19) =407344771a(20) =1412307481a(21) =4913508489a(22) =17148100569a(23) =60018592735a(24) =210619695913a(25) =740910077497