38102400

Appears in sequences

• Ratios of successive terms are 1,1,2,3,3,4,5,5,6,7,7,...at n=13A004395
• Triangle T(n,r), n>=0, r=n, n-1, ..., 1, 0; where T(n,r) = product of all possible sums of r numbers chosen from [1..n].at n=18A067050
• a(n) is the denominator of the coefficient of z^(2n-1) in the Maclaurin expansion of Sqrt[Pi]Erfi[z].at n=10A084253
• Array used for numerators of g.f.s for column sequences of array A078741 ((3,3)-Stirling2).at n=13A089517
• Product of all possible sums of two distinct numbers taken from among first n natural numbers.at n=4A093883
• T(n,k) = Sum of multinomial(n; n_1,n_2,...,n_k)^2, where the sum extends over all compositions (n_1,n_2,...,n_k) of n into exactly k nonnegative parts.at n=26A192722
• Number of primitive (=aperiodic) n-bead necklaces with colored beads of exactly 9 different colors.at n=2A254081
• Number of n X 3 arrays containing 3 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=8A268157
• Number of minimum dominating sets in the n X n black bishop graph.at n=19A323500
• Number of minimum dominating sets in the n X n white bishop graph.at n=18A323501
• a(n) = Product_{k=1..n} (Product_{j=1..k} (Product_{i=1..j} (i+j+k))).at n=3A324427
• Coreful 4-abundant numbers: numbers k such that csigma(k) > 4*k, where csigma(k) is the sum of the coreful divisors of k (A057723).at n=10A340110
• Triangular array read by rows. T(n,k) is the number of ways to form an ordered pair of n-permutations and then choose a size k subset of its common descent set, n >= 0, 0 <= k <= max{0,n-1}.at n=23A362589
• Numbers whose divisors have a mean abundancy index that is larger than 3.at n=24A374779