a(n) = (-1)^n + Sum_{k=0..n-1} binomial(n-1,k) * a(k) * a(n-k-1).

A309473

a(n) = (-1)^n + Sum_{k=0..n-1} binomial(n-1,k) * a(k) * a(n-k-1).

Terms

    a(0) =1a(1) =0a(2) =1a(3) =1a(4) =3a(5) =11a(6) =43a(7) =195a(8) =1063a(9) =6395a(10) =42371a(11) =311883a(12) =2501159a(13) =21672355a(14) =202544323a(15) =2028522067a(16) =21658255431a(17) =245738583307

External references