492030

Appears in sequences

• a(1)=1; a(2)=2; a(3)=3; a(n) = Sum_{k=3..n-1} (a(k) + a(k-1) + a(k-2)).at n=15A078344
• Number of solid standard Young tableaux of shape [[2*n,2],[2]].at n=18A215687