Binomial row sums of the Riordan matrix (1/(1-x),x/(1-x^2)) (A046854).

Terms

a(0) =1a(1) =2a(2) =4a(3) =11a(4) =32a(5) =92a(6) =271a(7) =814a(8) =2464a(9) =7508a(10) =23024a(11) =70952a(12) =219503a(13) =681358a(14) =2121116a(15) =6619571a(16) =20703040a(17) =64873328a(18) =203625604a(19) =640109128a(20) =2014951552a(21) =6350490808a(22) =20037015200a(23) =63284778256a(24) =200063948527a(25) =633007850942