a(0) = 1, a(n) = (-1)^n + (1/2) * Sum_{j=1..n} (1-(-1)^j-(-2)^j) * binomial(n,j) * a(n-j) for n > 0.

A370092

a(0) = 1, a(n) = (-1)^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) =1a(2) =3a(3) =16a(4) =105a(5) =856a(6) =8433a(7) =96916a(8) =1272225a(9) =18789136a(10) =308335713a(11) =5565837916a(12) =109603592145

External references