118524

Appears in sequences

• Number of rooted trees with 4 nodes of disjoint sets of labels with union {1..n}. If a node has an empty set of labels then it must have at least two children.at n=7A005174
• Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1), U=(1,2), or d=(1,-1) and having abscissa of first return equal to 3k.at n=31A108439
• Absolute value of coefficient of term [x^(n-3)] in characteristic polynomial of maximum matrix A of size n X n, where n >= 3. Maximum matrix A(i,j) is MAX(i,j), where indices i and j run from 1 to n.at n=13A112459
• Numbers that are equal to the product of the numerator and denominator of the harmonic mean of their divisors.at n=16A348828
• a(n) = Sum_{k=0..floor(2*n/3)} binomial(k+2,2) * binomial(k,2*n-3*k).at n=21A392269
• a(n) = Sum_{k=0..n} binomial(k+2,2) * binomial(k,3*n-3*k).at n=14A392313