a(0) = 1, a(n) = (1/2) * Sum_{j=1..n} (1-(-1)^j-(-2)^j) * binomial(n,j) * a(n-j) for n > 0.
A370456
a(0) = 1, a(n) = (1/2) * Sum_{j=1..n} (1-(-1)^j-(-2)^j) * binomial(n,j) * a(n-j) for n > 0.
Terms
- a(0) =1a(1) =2a(2) =6a(3) =29a(4) =192a(5) =1577a(6) =15516a(7) =178229a(8) =2339952a(9) =34559057a(10) =567117876a(11) =10237161629a(12) =201592448712
External references
- oeis: A370456