Number of odd-length branches starting at the root in all ordered trees with n edges.

A127540

Number of odd-length branches starting at the root in all ordered trees with n edges.

Terms

    a(0) =0a(1) =1a(2) =2a(3) =7a(4) =21a(5) =69a(6) =228a(7) =773a(8) =2659a(9) =9275a(10) =32715a(11) =116511a(12) =418377a(13) =1513163a(14) =5507242a(15) =20155583a(16) =74131537a(17) =273862373a(18) =1015762117a(19) =3781095113a(20) =14121051487a(21) =52895245133a(22) =198681804877a(23) =748162728797

External references