18863

Appears in sequences

• McKay-Thompson series of class 35A for Monster.at n=44A058640
• 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), (0, 1, 0), (1, 0, 1), (1, 1, -1), (1, 1, 0)}.at n=7A151135
• Number of odd numbers k such that difference between halving and tripling steps in Collatz (3x+1) trajectory of k is n.at n=28A222753
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 51", based on the 5-celled von Neumann neighborhood.at n=30A270020
• a(n) is the numerator of the imaginary part of Product_{k=1..n} (1 + i/k) where i is the imaginary unit.at n=11A370553