31776

Appears in sequences

• Square array read by antidiagonals giving number of binary trees of height n with k points on the n-th level (n,k>0).at n=25A065329
• q-factorial numbers 3!_q.at n=31A069778
• Coefficients of polynomials (in descending powers of x) P(n,x) := 1 + P(n-1,x)^2, where P(1,x) = x + 1.at n=32A158985
• Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k 3-term arithmetic progressions (n>=0; 0<=k<=floor((n-1)^2/4)).at n=46A162982
• n-th derivative of (((x^x)^x)^x)^x at x=1.at n=6A215706
• Sixth derivative of f_n at x=1, where f_n is the n-th of all functions that are representable as x^x^...^x with m>=1 x's and parentheses inserted in all possible ways.at n=8A215836
• The number of permutations of length n sortable by 3 prefix reversals (in the pancake sorting sense).at n=32A228398
• Numbers k where A098550(k)/k reaches a record high.at n=20A250127
• Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 subblock row and column sum equal to 0 2 3 6 or 7 and every 3 X 3 diagonal and antidiagonal sum not equal to 0 2 3 6 or 7.at n=14A252108
• Irregular triangular array, read by rows: row n shows the coefficients of the polynomial p(n,x) defined in Comments.at n=23A329429
• Triangle read by rows: T(n,m) (n >= m >= 1) = number of edges in the graph formed by drawing the line segments connecting any two of the (n+1) X (m+1) lattice points in an n X m grid of squares.at n=38A333278
• a(n) = m is the least m = b*c > a(n-1) such that (b+c)*n = m-1 where 1 < b <= c < m.at n=30A364171