a(1)=1; thereafter a(n) = (n/2)*Sum_{i=1..n-1} K(i,n-i)*a(i)*a(n-i), where K(i,j)=i/j+j/i+2.
A216733
a(1)=1; thereafter a(n) = (n/2)*Sum_{i=1..n-1} K(i,n-i)*a(i)*a(n-i), where K(i,j)=i/j+j/i+2.
Terms
- a(0) =1a(1) =4a(2) =54a(3) =1280a(4) =44500a(5) =2095632a(6) =127881376a(7) =9819500544a(8) =928097190000
External references
- oeis: A216733