601392

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, 0), (-1, 1, 0), (0, 0, -1), (0, 1, 1), (1, 0, 1)}.at n=10A150483
• a(n) is the number of 2 X 2 matrices over Z_p with determinant in {1,-1} where p = prime(n).at n=18A262354