581260

Appears in sequences

• Number of (2+1) X (n+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing x(i,j)+x(i-1,j) in the j direction.at n=20A250879
• 2^n+1 appears in A109732 at position a(n).at n=14A261414