19779

Appears in sequences

• Numbers n such that 3*10^n + 2*R_n - 1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=11A102966
• 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, -1, 0), (-1, 1, 0), (-1, 1, 1), (1, 0, 0)}.at n=10A148548
• G.f.: Product_{k>=1} (1 + x^k) / (1 - x^(k*(k+1))).at n=45A280424
• Number of dominating sets in the n-Sierpinski gasket graph.at n=2A347508