222280

Appears in sequences

• Triangular array read by rows: for n, k >= 1, a(n+1, 1) = 2*a(n, n); a(n+1, k+1) = a(n, k)+a(n+1, k).at n=42A129340
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, 0), (0, 1, 1), (1, 0, 1), (1, 1, -1)}.at n=9A150647