18455

Appears in sequences

• 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, -1), (-1, 0, 0), (1, -1, 0), (1, 1, -1), (1, 1, 1)}.at n=8A149614
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 131", based on the 5-celled von Neumann neighborhood.at n=30A270223
• a(n) is the number of squares in the n-th ring (n >= 0) of the Poincaré diagram of the order-5 square tiling of the hyperbolic plane (Schläfli symbol {4,5}).at n=6A390190