a(n) is the permanent of the n-th order Hankel matrix of Catalan numbers M(n) whose generic element is given by M(i,j) = A000108(i+j+4) with i,j = 0, ..., n-1.

A368022

a(n) is the permanent of the n-th order Hankel matrix of Catalan numbers M(n) whose generic element is given by M(i,j) = A000108(i+j+4) with i,j = 0, ..., n-1.

Terms

    a(0) =1a(1) =14a(2) =3612a(3) =14798454a(4) =930744290905

External references