a(n) = A123610(2*n+2,n)/(n+1) = A123618(n)/(n+1).

A123619

a(n) = A123610(2*n+2,n)/(n+1) = A123618(n)/(n+1).

Terms

    a(0) =1a(1) =2a(2) =13a(3) =98a(4) =884a(5) =8712a(6) =92033a(7) =1022450a(8) =11819620a(9) =141052808a(10) =1727897780a(11) =21634496072a(12) =275950213712

External references