Triangle read by rows: T(n,k) (0 <= k <= n) = Sum_{i=0..[k/2]} (-1)^i*binomial(k,2*i)*(2*i-1)!!*n^(k-2*i).
A244490
Triangle read by rows: T(n,k) (0 <= k <= n) = Sum_{i=0..[k/2]} (-1)^i*binomial(k,2*i)*(2*i-1)!!*n^(k-2*i).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =3a(6) =1a(7) =3a(8) =8a(9) =18a(10) =1a(11) =4a(12) =15a(13) =52a(14) =163a(15) =1a(16) =5a(17) =24a(18) =110a(19) =478a(20) =1950a(21) =1a(22) =6a(23) =35a(24) =198a(25) =1083a(26) =5706a(27) =28821a(28) =1a(29) =7
External references
- oeis: A244490