31818

Appears in sequences

• T(n,k)=Number of nXk arrays containing k copies of 0..n-1 with every element equal to at least one vertical or antidiagonal neighbor and the top left element equal to 0.at n=31A268159
• Number of 4Xn arrays containing n copies of 0..4-1 with every element equal to at least one vertical or antidiagonal neighbor and the top left element equal to 0.at n=4A268161
• Square array T(n,k), n>=0, k>=0, read by antidiagonals downwards, where column k is the expansion of 1/(1 - 9*x*(1 + x)^k)^(1/3).at n=50A361839
• Expansion of (1 - x)^2 * Sum_{j>=0} (x^j / (1 - Sum_{k=1..j} x^k)).at n=21A369116