a(n) = T(n,n-1), array T as in A050143. Also T(2n+1,n), array T as in A055807.

A050147

a(n) = T(n,n-1), array T as in A050143. Also T(2n+1,n), array T as in A055807.

Terms

    a(0) =1a(1) =3a(2) =12a(3) =56a(4) =280a(5) =1452a(6) =7700a(7) =41456a(8) =225648a(9) =1238420a(10) =6840988a(11) =37986984a(12) =211842696a(13) =1185635388a(14) =6655993380a(15) =37463920608a(16) =211350457824

External references