a(n) = Sum_{k=0..n} C(n,k)*sigma(n,k) for n>0 with a(0)=1.
A163190
a(n) = Sum_{k=0..n} C(n,k)*sigma(n,k) for n>0 with a(0)=1.
Terms
- a(0) =1a(1) =2a(2) =13a(3) =72a(4) =722a(5) =7808a(6) =122538a(7) =2097280a(8) =43444163a(9) =1000262656a(10) =25997950850a(11) =743008372736
External references
- oeis: A163190