25724

Appears in sequences

• Fine's sequence (or Fine numbers): number of relations of valence >= 1 on an n-set; also number of ordered rooted trees with n nodes having root of even degree.at n=12A000957
• Powers of fourth root of 15 rounded down.at n=15A018087
• Powers of fourth root of 15 rounded to nearest integer.at n=15A018088
• a(n) = (2*n-1)*(n^2 -n +2)/2.at n=29A063488
• Triangle T(n,k) giving number of Dyck paths of length 2n with exactly k hills (0 <= k <= n).at n=66A065600
• Triangle T(n,k) giving number of hill-free Dyck paths of length 2n and having height of first peak equal to k.at n=56A065602
• Expansion of (1-2*x-sqrt(1-4*x))/(x^2 * (1+2*x+sqrt(1-4*x))).at n=9A104629
• A bisection of A000957.at n=6A138413
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (0, 0, 1), (0, 1, -1), (1, 0, 1)}.at n=8A150395
• Number of nX5 0..2 arrays with no more than floor(nX5/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..2 order.at n=4A222646
• T(n,k)=Number of nXk 0..2 arrays with no more than floor(nXk/2) elements unequal to at least one horizontal, vertical or antidiagonal neighbor, with new values introduced in row major 0..2 order.at n=40A222649
• Number of (2+1) X (n+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or antidiagonally, with no adjacent elements equal.at n=10A232591
• Lengths of largest face diagonal in primitive Euler bricks or Pythagorean cuboids: possible values of max(d, e, f) for solutions to a^2 + b^2 = d^2, a^2 + c^2 = e^2, b^2 + c^2 = f^2 in coprime positive integers a, b, c, d, e, f.at n=29A306120