21146

Appears in sequences

• a(n) = B(n) - 1, where B(n) = Bell numbers, A000110.at n=7A058692
• a(n) = (1/40320)*8^n + (1/1440)*6^n + (1/360)*5^n + (1/64)*4^n + (11/180)*3^n + (53/288)*2^n + 103/280. Partial sum of Stirling numbers of second kind S(n,i), i=1..8 (i.e., a(n) = Sum_{i=1..8} S(n,i)).at n=8A099263
• Triangle of partial sums of Stirling numbers of 2nd kind (A008277): T(n,k) = Sum_{i=1..k} Stirling2(n,i), 1<=k<=n.at n=43A102661
• A triangular array of numbers related to factorization and number of parts in Murasaki diagrams.at n=47A133611
• Triangle read by rows, A008277 * A000012.at n=37A137650
• a(n) = 36*n^2 - 55*n + 21.at n=24A157262
• Number of partitions of n having no more odd than even parts.at n=43A171966
• Permutation trees of power n and height k.at n=38A179454
• Number of set partitions of {1,...,n} that avoid enhanced 5-crossings (or 5-nestings).at n=9A192865
• Number of n X n symmetric 0..1 arrays with each element equal to the sum mod 2 of two of its horizontal and vertical neighbors.at n=5A193118
• T(n,k)=Number of nXk 0..7 arrays with every 2X2 subblock containing exactly one value repeat, and new values 0..7 introduced in row major order.at n=36A209527
• T(n,k) = number of nonnegative integer arrays of length n+k-1 with new values 0 upwards introduced in order, and containing the value k-1.at n=43A211561
• Number G(n,k) of set partitions of {1,...,n} into sets of size at most k; triangle G(n,k), n>=0, 0<=k<=n, read by rows.at n=53A229223
• The partition function G(n,8).at n=9A229225
• a(n) = (5*n^9 - 30*n^7 + 63*n^5 - 50*n^3 + 12*n)/360.at n=5A239094
• Second partial sums of seventh powers (A001015).at n=3A250212
• a(n) = 1*4^n + 2*3^n + 3*2^n + 4*1^n.at n=7A254030
• Number of primitive (aperiodic) palindromic structures of length n using an infinite alphabet.at n=16A284841
• Number of primitive (period n) periodic palindromic structures of length n using an infinite alphabet.at n=17A285042
• Number of set partitions of [n] such that all absolute differences between least elements of consecutive blocks are <= seven.at n=9A287257