a(n) = Sum_{k=1..n} |Stirling1(n,k)| * Catalan(k-1).

A355292

a(n) = Sum_{k=1..n} |Stirling1(n,k)| * Catalan(k-1).

Terms

    a(0) =1a(1) =2a(2) =7a(3) =34a(4) =208a(5) =1521a(6) =12871a(7) =123306a(8) =1316316a(9) =15471114a(10) =198319614a(11) =2751524557a(12) =41058030388a(13) =655427422651

External references