cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A059060 Card-matching numbers (Dinner-Diner matching numbers).

Original entry on oeis.org

1, 0, 0, 0, 0, 1, 1, 0, 16, 0, 36, 0, 16, 0, 1, 346, 1824, 4536, 7136, 7947, 6336, 3936, 1728, 684, 128, 48, 0, 1, 748521, 3662976, 8607744, 12880512, 13731616, 11042688, 6928704, 3458432, 1395126, 453888, 122016, 25344, 4824, 512, 96, 0, 1, 3993445276
Offset: 0

Views

Author

Barbara Haas Margolius (margolius(AT)math.csuohio.edu)

Keywords

Comments

This is a triangle of card matching numbers. A deck has n kinds of cards, 4 of each kind. The deck is shuffled and dealt in to n hands with 4 cards each. A match occurs for every card in the j-th hand of kind j. Triangle T(n,k) is the number of ways of achieving exactly k matches (k=0..4n). The probability of exactly k matches is T(n,k)/((4n)!/(4!)^n).
Rows have lengths 1,5,9,13,...
Analogous to A008290 - Zerinvary Lajos, Jun 22 2005

Examples

			There are 16 ways of matching exactly 2 cards when there are 2 different kinds of cards, 4 of each so T(2,2)=16.
From _Joerg Arndt_, Nov 08 2020: (Start)
The first few rows are
1
0, 0, 0, 0, 1
1, 0, 16, 0, 36, 0, 16, 0, 1
346, 1824, 4536, 7136, 7947, 6336, 3936, 1728, 684, 128, 48, 0, 1
748521, 3662976, 8607744, 12880512, 13731616, 11042688, 6928704, 3458432, 1395126, 453888, 122016, 25344, 4824, 512, 96, 0, 1
3993445276, 18743463360, 42506546320, 61907282240, 64917874125, 52087325696, 33176621920, 17181584640, 7352761180, 2628808000, 790912656, 201062080, 43284010, 7873920, 1216000, 154496, 17640, 1280, 160, 0, 1 (End)
		

References

  • F. N. David and D. E. Barton, Combinatorial Chance, Hafner, NY, 1962, Ch. 7 and Ch. 12.
  • J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, pp. 174-178.
  • R. P. Stanley, Enumerative Combinatorics Volume I, Cambridge University Press, 1997, p. 71.

Crossrefs

Programs

  • Maple
    p := (x,k)->k!^2*sum(x^j/((k-j)!^2*j!),j=0..k); R := (x,n,k)->p(x,k)^n; f := (t,n,k)->sum(coeff(R(x,n,k),x,j)*(t-1)^j*(n*k-j)!,j=0..n*k);
    for n from 0 to 5 do seq(coeff(f(t,n,4),t,m)/4!^n,m=0..4*n); od;
  • Mathematica
    p[x_, k_] := k!^2*Sum[ x^j/((k-j)!^2*j!), {j, 0, k}]; r[x_, n_, k_] := p[x, k]^n; f[t_, n_, k_] := Sum[ Coefficient[r[x, n, k], x, j]*(t-1)^j*(n*k-j)!, {j, 0, n*k}]; Table[ Coefficient[f[t, n, 4], t, m]/4!^n, {n, 0, 5}, {m, 0, 4*n}] // Flatten (* Jean-François Alcover, Feb 22 2013, translated from Maple *)

Formula

G.f.: sum(coeff(R(x, n, k), x, j)*(t-1)^j*(n*k-j)!, j=0..n*k) where n is the number of kinds of cards, k is the number of cards of each kind (here k is 4) and R(x, n, k) is the rook polynomial given by R(x, n, k)=(k!^2*sum(x^j/((k-j)!^2*j!))^n (see Stanley or Riordan). coeff(R(x, n, k), x, j) indicates the j-th coefficient on x of the rook polynomial.