166924800

Appears in sequences

• E.g.f. (1-x)/(1-x-2x^3).at n=10A052601
• Triangle read by rows: T(n,k) = count of increasing runs in two concatenated k-permutations of [n].at n=26A122823
• a(n) = n! * A000110(n) where A000110 is the sequence of Bell numbers.at n=8A137341
• Number T(n,k) of colored set partitions of [n] where exactly k colors are used for the elements; triangle T(n,k), n>=0, 0<=k<=n, read by rows.at n=44A323099
• Number T(n,k) of colored set partitions of [n] where elements of subsets have distinct colors and exactly k colors are used; triangle T(n,k), n>=0, 0<=k<=n, read by rows.at n=44A323128
• a(n) = n! * Sum_{k=1..n} k/floor(n/k).at n=9A345684