a(n) = Sum_{k=n..2*n} |Stirling1(2*n, k) * Stirling1(k, n)|.
A341589
a(n) = Sum_{k=n..2*n} |Stirling1(2*n, k) * Stirling1(k, n)|.
Terms
- a(0) =1a(1) =2a(2) =40a(3) =1485a(4) =81088a(5) =5856900a(6) =526685269a(7) =56704848200
External references
- oeis: A341589