First row of A113435.

Terms

a(0) =1a(1) =2a(2) =7a(3) =26a(4) =98a(5) =371a(6) =1406a(7) =5329a(8) =20196a(9) =76532a(10) =289997a(11) =1098826a(12) =4163483a(13) =15775426a(14) =59772826a(15) =226477879a(16) =858118966a(17) =3251390237a(18) =12319431012a(19) =46677994276a(20) =176861668393a(21) =670124115506