Delannoy Numbers

Questions about Delannoy numbers, their properties, recurrence relations, and applications in combinatorics

5 Questions Published

Questions

Question 1 Multiple Choice (Single Answer)

What is the Delannoy number D(n, m)?

  1. The number of paths from (0, 0) to (n, m) in the grid, where each step is either right or up.
  2. The number of paths from (0, 0) to (n, m) in the grid, where each step is either right or down.
  3. The number of paths from (0, 0) to (n, m) in the grid, where each step is either right or diagonal.
  4. The number of paths from (0, 0) to (n, m) in the grid, where each step is either up or diagonal.
Question 2 Multiple Choice (Single Answer)

What is the recurrence relation for the Delannoy numbers?

  1. D(n, m) = D(n - 1, m) + D(n, m - 1)
  2. D(n, m) = D(n - 1, m) - D(n, m - 1)
  3. D(n, m) = D(n - 1, m) * D(n, m - 1)
  4. D(n, m) = D(n - 1, m) / D(n, m - 1)
Question 3 Multiple Choice (Single Answer)

What is the generating function for the Delannoy numbers?

  1. F(x, y) = (1 - x - y)^-1
  2. F(x, y) = (1 + x + y)^-1
  3. F(x, y) = (1 - x * y)^-1
  4. F(x, y) = (1 + x * y)^-1
Question 4 Multiple Choice (Single Answer)

What is the asymptotic formula for the Delannoy numbers?

  1. D(n, m) ~ (2 / sqrt(pi)) * n^(3/2) * m^(3/2)
  2. D(n, m) ~ (2 / sqrt(pi)) * n^(1/2) * m^(1/2)
  3. D(n, m) ~ (2 / sqrt(pi)) * n^(5/2) * m^(5/2)
  4. D(n, m) ~ (2 / sqrt(pi)) * n^(7/2) * m^(7/2)
Question 5 Multiple Choice (Single Answer)

What are some applications of the Delannoy numbers?

  1. Counting lattice paths
  2. Counting tilings
  3. Counting permutations
  4. Counting graphs