512050

Appears in sequences

• a(n) = binomial(n,3)*binomial(n-1,3)/4.at n=18A006542
• Triangle T(n, k) = A001263(n*f(n,k) + 1, f(n,k) + 1), where f(n, k) = k if k <= floor(n/2) otherwise n-k, read by rows.at n=31A157243
• Triangle T(n, k) = A001263(n*f(n,k) + 1, f(n,k) + 1), where f(n, k) = k if k <= floor(n/2) otherwise n-k, read by rows.at n=32A157243
• n/2 analog of Keith numbers.at n=10A282766
• 1/15840 of the volume of a primitive 3-simplex.at n=14A295507