a(n) = Sum_{k=0..n} (-1)^(n-k)*C(n,k)*sigma(n,k) for n>0 with a(0)=1.
A163191
a(n) = Sum_{k=0..n} (-1)^(n-k)*C(n,k)*sigma(n,k) for n>0 with a(0)=1.
Terms
- a(0) =1a(1) =0a(2) =1a(3) =8a(4) =82a(5) =1024a(6) =15690a(7) =279936a(8) =5771363a(9) =134218240a(10) =3487832978a(11) =100000000000
External references
- oeis: A163191