Number of ordered trees with n edges such that non-leaf vertices at even (odd) level have an odd (even) number of children.

A248096

Number of ordered trees with n edges such that non-leaf vertices at even (odd) level have an odd (even) number of children.

Terms

    a(0) =1a(1) =1a(2) =0a(3) =2a(4) =2a(5) =6a(6) =14a(7) =30a(8) =80a(9) =191a(10) =482a(11) =1253a(12) =3178a(13) =8370a(14) =21908a(15) =57861a(16) =154262a(17) =411724a(18) =1106990a(19) =2986434a(20) =8085282a(21) =21978895a(22) =59905632a(23) =163786142a(24) =448976298a(25) =1233655230a(26) =3397615736a(27) =9376447532a(28) =25926798104a(29) =71819992609

External references