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.

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A372307 Square array read by antidiagonals: T(n,k) is the number of derangements of a multiset comprising n repeats of a k-element set.

Original entry on oeis.org

1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 2, 1, 0, 1, 1, 9, 10, 1, 0, 1, 1, 44, 297, 56, 1, 0, 1, 1, 265, 13756, 13833, 346, 1, 0, 1, 1, 1854, 925705, 6699824, 748521, 2252, 1, 0, 1, 1, 14833, 85394646, 5691917785, 3993445276, 44127009, 15184, 1, 0, 1
Offset: 0

Views

Author

Jeremy Tan, Apr 26 2024

Keywords

Comments

A deck has k suits of n cards each. The deck is shuffled and dealt into k hands of n cards each. A match occurs for every card in the i-th hand of suit i. T(n,k) is the number of ways of achieving no matches. The probability of no matches is T(n,k)/((n*k)!/n!^k).
T(n,k) is the maximal number of totally mixed Nash equilibria in games of k players, each with n+1 pure options.

Examples

			Square array T(n,k) begins:
  1, 1, 1,      1,            1,                   1, ...
  1, 0, 1,      2,            9,                  44, ...
  1, 0, 1,     10,          297,               13756, ...
  1, 0, 1,     56,        13833,             6699824, ...
  1, 0, 1,    346,       748521,          3993445276, ...
  1, 0, 1,   2252,     44127009,       2671644472544, ...
  1, 0, 1,  15184,   2750141241,    1926172117389136, ...
  1, 0, 1, 104960, 178218782793, 1463447061709156064, ...
		

Crossrefs

Columns 0-4 give A000012, A000007, A000012, A000172, A371252.
Main diagonal gives A375778.

Programs

  • Maple
    A:= (n, k)-> (-1)^(n*k)*int(exp(-x)*orthopoly[L](n, x)^k, x=0..infinity):
    seq(seq(A(n, d-n), n=0..d), d=0..10);  # Alois P. Heinz, Aug 27 2024
  • Mathematica
    Table[Abs[Integrate[Exp[-x] LaguerreL[n, x]^(s-n), {x, 0, Infinity}]], {s, 0, 9}, {n, 0, s}] // Flatten
  • Python
    # See link.

Formula

T(n,k) = (-1)^(n*k) * Integral_{x=0..oo} exp(-x)*L_n(x)^k dx, where L_n(x) is the Laguerre polynomial of degree n (Even and Gillis).
T(n,k) ~ A089759(n,k)/exp(n).

A059074 Number of derangements of a multiset comprising 4 repeats of an n-element set.

Original entry on oeis.org

1, 0, 1, 346, 748521, 3993445276, 45131501617225, 964363228180815366, 35780355973270898382001, 2158610844939711892526650456, 201028342764877992289387752167601, 27708893753238763155350683269145066450, 5459844285803153226360263675364357481841881
Offset: 0

Views

Author

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

Keywords

Comments

Previous name was: Card-matching numbers (Dinner-Diner 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. A(n) is the number of ways of achieving no matches. The probability of no matches is A(n)/((4n)!/4!^n).
Number of fixed-point-free permutations of n distinct letters (ABCD...), each of which appears 4 times: 1111, 11112222, 111122223333, 1111222233334444, etc. If there is only one letter of each type we get A000166 - Zerinvary Lajos, Nov 05 2006
a(n) is the maximal number of totally mixed Nash equilibria in games of n players, each with 5 pure options. [Raimundas Vidunas, Jan 22 2014]

Examples

			There are 346 ways of achieving zero matches when there are 4 cards of each kind and 3 kinds of card so A(3)=346.
		

References

  • F. N. David and D. E. Barton, Combinatorial Chance, Hafner, NY, 1962, Ch. 7 and Ch. 12.
  • R.D. McKelvey and A. McLennan, The maximal number of regular totally mixed Nash equilibria, J. Economic Theory, 72:411-425, 1997.
  • S. G. Penrice, Derangements, permanents and Christmas presents, The American Mathematical Monthly 98(1991), 617-620.
  • 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); seq(f(0,n,4)/4!^n,n=0..18);
  • 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[f[0, n, 4]/4!^n, {n, 0, 18}] // Flatten (* Jean-François Alcover, Oct 21 2013, after Maple *)
    Table[Integrate[Exp[-x] LaguerreL[4, x]^n, {x, 0, Infinity}], {n, 0, 16}] (* Jeremy Tan, Apr 25 2024 *)
    rec = 3*(128*n^3 - 560*n^2 + 840*n - 537)*a[n] - n*(4096*n^6 - 24064*n^5 + 62720*n^4 - 92992*n^3 + 75248*n^2 - 38670*n + 4179)*a[n-1] - 2*n*(n-1)*(18432*n^5 - 99072*n^4 + 197120*n^3 - 191776*n^2 + 144568*n - 92531)*a[n-2] + 48*n*(n-1)*(n-2)*(768*n^4 - 2976*n^3 + 3104*n^2 - 2438*n + 1583)*a[n-3] + 288*n*(n-1)*(n-2)*(n-3)*(128*n^3 - 176*n^2 + 104*n - 129)*a[n-4] == 8192*n^6 - 28672*n^5 + 23680*n^4 - 7904*n^3 + 1416*n^2 + 14382*n - 1611;
    RecurrenceTable[{rec, a[0] == 1, a[1] == 0, a[2] == 1, a[3] == 346}, a, {n, 0, 16}] (* Jeremy Tan, Apr 25 2024 *)
  • Python
    def A059074(n):
        l = [1, 0, 1, 346]
        for k in range(4, n+1):
            num = (((((8192*k-28672)*k+23680)*k-7904)*k+1416)*k+14382)*k-1611 \
                + k*((((((4096*k-24064)*k+62720)*k-92992)*k+75248)*k-38670)*k+4179)*l[-1] \
                + 2*k*(k-1)*(((((18432*k-99072)*k+197120)*k-191776)*k+144568)*k-92531)*l[-2] \
                - 48*k*(k-1)*(k-2)*((((768*k-2976)*k+3104)*k-2438)*k+1583)*l[-3] \
                - 288*k*(k-1)*(k-2)*(k-3)*(((128*k-176)*k+104)*k-129)*l[-4]
            r = num // (3*(((128*k-560)*k+840)*k-537))
            l.append(r)
        return l[n] # Jeremy Tan, Apr 25 2024

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 (3 in this case) 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 coefficient for x^j of the rook polynomial.
From Jeremy Tan, Apr 25 2024: (Start)
a(n) = Integral_{x=0..oo} exp(-x)*L_4(x)^n dx, where L_n(x) is the Laguerre polynomial of degree n (Even and Gillis).
D-finite with recurrence 3*(128*n^3 - 560*n^2 + 840*n - 537)*a(n) - n*(4096*n^6 - 24064*n^5 + 62720*n^4 - 92992*n^3 + 75248*n^2 - 38670*n + 4179)*a(n-1) - 2*n*(n-1)*(18432*n^5 - 99072*n^4 + 197120*n^3 - 191776*n^2 + 144568*n - 92531)*a(n-2) + 48*n*(n-1)*(n-2)*(768*n^4 - 2976*n^3 + 3104*n^2 - 2438*n + 1583)*a(n-3) + 288*n*(n-1)*(n-2)*(n-3)*(128*n^3 - 176*n^2 + 104*n - 129)*a(n-4) = 8192*n^6 - 28672*n^5 + 23680*n^4 - 7904*n^3 + 1416*n^2 + 14382*n - 1611 (Ekhad).
a(n) ~ A014608(n)/exp(4) ~ n^(4*n)*(32/3)^n*sqrt(8*Pi*n)/exp(4*n+4). (End)

Extensions

Name changed by Jeremy Tan, Apr 25 2024
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