478192

Appears in sequences

• a(n) = C(1,1) + C(3,2) + C(5,3) + ... + C(2*n-1,n).at n=10A079309
• Expansion of (1+2x-sqrt(1-4x^2))/(2(1-x^2)*sqrt(1-4x^2)).at n=22A174783
• Number of base pyramids in all length n left factors of Dyck paths.at n=22A191790
• Number of n X 5 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 0 1 and 1 0 1 vertically.at n=18A207166
• a(n) = Sum_{k=1..n-1} ((-1)^(k+n+1)*binomial(k,floor(k/2))).at n=22A332754
• Number of nonempty subsets of {1..n} with median n/2.at n=22A361801
• Number of nonempty subsets of {1..n} with median n/2.at n=23A361801