4540386

Appears in sequences

• a(n) = 2^(2*n+1) - C(2*n+3,n+1) + C(2*n+1,n).at n=11A006419
• a(n) = Sum_{k=0..10} binomial(n,k).at n=24A008863
• Expansion of g.f. (1+z)^(24)/(1-z).at n=10A171445
• Number of valleys at level 0 in all dispersed Dyck paths of length n (i.e., in all Motzkin paths of length n with no (1,0) steps at positive heights).at n=24A191389