220800

Appears in sequences

• Variance of time for a random walk starting at 0 to reach one of the boundaries at +n or -n for the first time.at n=24A072819
• G.f. satisfies: A(x) = P(x*A(x)^2) where A(x/P(x)^2) = P(x) is the g.f. for Partition numbers (A000041).at n=8A171802
• a(1) = 1, a(2) = 3, and from then on alternatively subtract and multiply two previous terms.at n=9A248479
• Numbers k such that (28*10^k + 173)/3 is prime.at n=33A272537
• The number of F_2 graphs on { 1, 2, ..., n } with a unique cycle of weight 1, which corresponds to the number of reflectable bases of the root system of type D_n.at n=5A320064