38910

Appears in sequences

• a(n+2) = 3*a(n) - a(n-2) with a(0) = 1, a(1) = 3, a(2) = 6.at n=17A018186
• Expansion of (1-x^2)/(1-3*x-x^2).at n=9A052906
• Numbers whose set of base 6 digits is {0,5}.at n=34A097252
• Fixed-j dispersion for Q = 13: array D(g,h) (g, h >= 1), read by ascending antidiagonals.at n=25A120862
• 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, 1), (0, 1, -1), (1, 0, 0), (1, 0, 1)}.at n=8A150522
• a(n) = (n-2)*(n-3)*2^(n-2)+2^n-2.at n=10A217528
• List of quadruples (r,s,t,u): the matrix M = [[4,12,9][2,5,3][1,2,1]] is raised to successive powers, then (r,s,t,u) are the square roots of M[3,1], M[3,3], M[1,1], M[1,3] respectively.at n=39A249579
• List of quadruples (r,s,t,u): the matrix M = [[4,12,9][2,5,3][1,2,1]] is raised to successive negative powers, then (r,s,t,u) are the square roots of M[1,3], M[1,1], M[3,3], M[3,1] respectively.at n=32A249580
• a(n) is the number of free polyominoes with sprawl n.at n=30A338213