681080400

Appears in sequences

• a(n) = (2n)!/2^n.at n=7A000680
• Joffe's central differences of 0, A241171(n,n-1).at n=6A002456
• Expand sin x / exp x = x-x^2+x^3/3-x^5/30+... and invert nonzero coefficients.at n=14A007415
• Expansion of E.g.f.: (1 + x)/(1 + x + x^2/2).at n=14A009014
• Exponential generating function is tanh(log(1+x)).at n=14A009775
• Denominators of Taylor series for exp(x)*sin(x).at n=14A046979
• a(n) = (4n+2)!/2^(2n+1).at n=3A052277
• Square array read by antidiagonals of number of ways of dividing n*k labeled items into n labeled boxes with k items in each box.at n=34A060538
• a(n) = (7n)!/n!^7.at n=2A071549
• Denominators used in the computation of the column sequences of array A078739 ((2,2)-Stirling2).at n=14A089512
• Table T(n,k), 0<=k, 0<=n, read by antidiagonals, defined by T(n,k) = (k*n)! / (n!)^k.at n=47A089759
• a(n) = n! / 2^floor(n/2).at n=14A090932
• a(n) = n(n-1)(n-3)(n-6)...(n-t), where t is the largest triangular number less than n; number of factors in the product is ceiling((sqrt(1+8*n)-1)/2).at n=27A094261
• Denominators associated with Taylor series expansion of inverse error function. See A092676 for numerators and further information.at n=7A132467
• Number of 2*n X n 0..1 arrays with row sums 6 and column sums 12.at n=6A172552
• Number of 7*n X 14 0..1 arrays with row sums 2 and column sums n.at n=0A172604
• Number of 7*n X 14 0..2 arrays with row sums 2 and column sums n.at n=0A172709
• Number of permutations of 2 copies of 1..n with all adjacent differences <= 6 in absolute value.at n=7A177287
• Number of permutations of 2 copies of 1..n with all adjacent differences <= 7 in absolute value.at n=7A177288
• Number of permutations of 2 copies of 1..n with all adjacent differences <= 8 in absolute value.at n=7A177289