260720

Appears in sequences

• Number of intransitive (or alternating, or Stanley) trees: vertices are [0,n] and for no i<j<k are both (i,j) and (j,k) edges.at n=8A007889
• a(n) = A026626(2*n, n).at n=10A026627
• a(n) = A026626(n, floor(n/2)).at n=20A026632
• Solution to the Dancing School Problem with 7 girls and n+7 boys: f(7,n).at n=7A079912
• Solution to the Dancing School Problem with n girls and n+7 boys: f(n,7).at n=6A079926
• First term of n-th difference sequence of (round(k*phi)), phi = golden ratio = (1+sqrt(5))/2, k >= 0.at n=20A325844