461890

Appears in sequences

• a(n) = 6*(2*n+1)! / ((n!)^2*(n+3)).at n=9A007946
• Central numbers in the (2,3)-Pascal triangle A029600.at n=10A029609
• Expansion of 1/(2*x) * (1/(1-4*x)^(3/2)-1).at n=8A033876
• 1/256 of tenth unsigned column of triangle A053120 (T-Chebyshev, rising powers, zeros omitted).at n=12A054333
• Product of primes < n that do not divide n.at n=20A066838
• a(n) is the least k which is the start of n consecutive integers each with a different number, 1 through n, of distinct prime factors.at n=6A068069
• Denominators of 2*Sum_{k=1..n} 1/binomial(2*k,k), n >= 1.at n=10A130546
• Denominators of 6*(sum(1/binomial(2*k,k),k=1..n)-1/3), n>=1.at n=10A130548
• A triangle of coefficients: T(n,m) = (2*n + 2*m + 3)! / (2*(2*m + 1)!*(2*n + 1)!).at n=14A143083
• Number of walks within N^2 (the first quadrant of Z^2) starting and ending at (0,0) and consisting of 2 n steps taken from {(-1, -1), (-1, 0), (-1, 1), (1, 0)}.at n=8A151341
• The radical of the swinging factorial A056040 for odd indices.at n=9A163640
• The radical of the swinging factorial A056040.at n=19A163641
• Denominator of the n-th term of the inverse binomial transform of 1, 1/2, B_4, B_6, B_8,..., a modified Bernoulli sequence.at n=10A174276
• a(n) = 2^n*binomial((n + 1 + (n mod 2))/2, 1/2).at n=17A242172
• a(n) = 6*(n+1)!/((3+floor(n/2))*(floor(n/2)!)^2).at n=18A242986
• Expansion of (x*(1-4*x^2)^(-3/2) + (1-4*x^2)^(-1/2) + x + 1)/2.at n=19A275324
• a(n) = (20*n)!*(3*n)!/((10*n)!*(9*n)!*(4*n)!).at n=1A295475
• Squarefree part of 1!*2!*3!*...*n!: The product of factorials one through n divided by its largest square divisor.at n=37A299700
• a(n) = (10*n)!*(3*n/2)!/((5*n)!*(9*n/2)!*(2*n)!).at n=2A364181
• a(1) = 1; for n > 1, a(n) = A055231(a(n-1) * n), where A055231(k) is the powerfree part of k.at n=18A368823