273273

Appears in sequences

• a(n) = binomial(n+5,5) * binomial(n+5,4)/(n+5).at n=10A006857
• Number of nonempty subsets of {1,2,...,n} in which exactly 1/5 of the elements are <= n/2.at n=26A047165
• Number of nonempty subsets of {1,2,...,n} in which exactly 1/5 of the elements are <= (n-1)/2.at n=26A047176
• a(n) = binomial(m+n-1,n)^2 - binomial(m+n,n+1)*binomial(m+n-2,n-1) with m=12.at n=4A140925
• Number of 4 X 10 matrices with elements in 0..n with each row and each column in nondecreasing order. 4,10,n can be permuted, see formula.at n=2A140927
• Triangle T(n, k) = binomial(2*n, 2*k)*binomial(2*n+1, 2*k+1)/(2*n-2*k+1), read by rows.at n=30A155516
• Triangle T(n, k) = binomial(2*n, 2*k)*binomial(2*n+1, 2*k+1)/(2*n-2*k+1), read by rows.at n=33A155516
• Triangle read by rows: T(n,r) = binomial(n,r)*binomial(2*n-3*r-4,n-2*r-2)/(n-r-1), n >= 2, r = 0..floor(n/2)-1.at n=53A259097
• Triangle read by rows: T(n,k) = generalized binomial coefficients (n,k)_10 (n >= 0, 0 <= k <= n).at n=23A342889
• Triangle read by rows: T(n,k) = generalized binomial coefficients (n,k)_10 (n >= 0, 0 <= k <= n).at n=25A342889