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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A059056 Penrice Christmas gift numbers, Card-matching numbers (Dinner-Diner matching numbers): Triangle T(n,k) = number of ways to get k matches for a deck with n cards, 2 of each kind.

Original entry on oeis.org

1, 0, 0, 1, 1, 0, 4, 0, 1, 10, 24, 27, 16, 12, 0, 1, 297, 672, 736, 480, 246, 64, 24, 0, 1, 13756, 30480, 32365, 21760, 10300, 3568, 970, 160, 40, 0, 1, 925705, 2016480, 2116836, 1418720, 677655, 243360, 67920, 14688, 2655, 320, 60, 0, 1
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, 2 of each kind. The deck is shuffled and dealt in to n hands with 2 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..2n). The probability of exactly k matches is T(n,k)/((2n)!/2^n).
Rows are of length 1,3,5,7,... = A005408(n). [Edited by M. F. Hasler, Sep 21 2015]
Analogous to A008290. - Zerinvary Lajos, Jun 10 2005

Examples

			There are 4 ways of matching exactly 2 cards when there are 2 different kinds of cards, 2 of each in each of the two decks so T(2,2)=4.
Triangle begins:
1
"0", 0, 1
1, '0', "4", 0, 1
10, 24, 27, '16', "12", 0, 1
297, 672, 736, 480, 246, '64', "24", 0, 1
13756, 30480, 32365, 21760, 10300, 3568, 970, '160', "40", 0, 1
925705, 2016480, 2116836, 1418720, 677655, 243360, 67920, 14688, 2655, '320', "60", 0, 1
Diagonal " ": T(n,2n-2) = 0, 4, 12, 24, 40, 60, 84, 112, 144, ... equals A046092
Diagonal ' ': T(n,2n-3) = 0, 16, 64, 160, 320, 560, 896, 1344, ... equals A102860
		

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 7 do seq(coeff(f(t,n,2),t,m)/2^n,m=0..2*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, 2]/2^n, t, m], {n, 0, 6}, {m, 0, 2*n}] // Flatten
    (* Jean-François Alcover, Sep 17 2012, 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 2) 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.

Extensions

Additional comments from Zerinvary Lajos, Jun 18 2007
Edited by M. F. Hasler, Sep 21 2015

A000459 Number of multiset permutations of {1, 1, 2, 2, ..., n, n} with no fixed points.

Original entry on oeis.org

1, 0, 1, 10, 297, 13756, 925705, 85394646, 10351036465, 1596005408152, 305104214112561, 70830194649795010, 19629681235869138841, 6401745422388206166420, 2427004973632598297444857, 1058435896607583305978409166, 526149167104704966948064477665
Offset: 0

Views

Author

Keywords

Comments

Original definition: Number of permutations with no hits on 2 main diagonals. (Identical to definition of A000316.) - M. F. Hasler, Sep 27 2015
Card-matching numbers (Dinner-Diner matching numbers): A deck has n kinds of cards, 2 of each kind. The deck is shuffled and dealt in to n hands with 2 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)/((2n)!/2!^n).
Also, Penrice's Christmas gift numbers (see Penrice 1991).
a(n) is the maximal number of totally mixed Nash equilibria in games of n players, each with 3 pure options. - Raimundas Vidunas, Jan 22 2014

Examples

			There are 297 ways of achieving zero matches when there are 2 cards of each kind and 4 kinds of card so a(4)=297.
From _Peter Bala_, Jul 08 2014: (Start)
a(3) = 10: the 10 permutations of the multiset {1,1,2,2,3,3} that have no fixed points are
{2,2,3,3,1,1}, {3,3,1,1,2,2}
{2,3,1,3,1,2}, {2,3,1,3,2,1}
{2,3,3,1,1,2}, {2,3,3,1,2,1}
{3,2,1,3,1,2}, {3,2,1,3,2,1}
{3,2,3,1,1,2}, {3,2,3,1,2,1}
(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.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Programs

  • Magma
    I:=[0,1]; [n le 2 select I[n] else n*(2*n-1)*Self(n-1)+2*n*(n-1)*Self(n-2)-(2*n-1): n in [1..30]]; // Vincenzo Librandi, Sep 28 2015
    
  • 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,2)/2!^n,n=0..18);
  • Mathematica
    RecurrenceTable[{(2*n+3)*a[n+3]==(2*n+5)^2*(n+2)*a[n+2]+(2*n+3)*(n+2)*a[n+1]-2*(2*n+5)*(n+1)*(n+2)*a[n],a[1]==0,a[2]==1,a[3]==10},a,{n,1,25}] (* Vaclav Kotesovec, Aug 31 2012 *)
    a[n_] := a[n] = n*(2*n-1)*a[n-1] + 2*n*(n-1)*a[n-2] - (2*n-1); a[0] = 1; a[1] = 0; a[2] = 1; Table[a[n], {n, 0, 14}] (* Jean-François Alcover, Mar 04 2013 *)
    a[n_] := Sum[(2*(n-m))! / 2^(n-m) Binomial[n, m] Hypergeometric1F1[m-n, 2*(m - n), -4], {m, 0, n}]; Table[a[n], {n, 0, 16}] (* Peter Luschny, Nov 15 2023 *)
  • PARI
    a(n) = (2^n*round(2^(n/2+3/4)*Pi^(-1/2)*exp(-2)*n!*besselk(1/2+n,2^(1/2))))/2^n;
    vector(15, n, a(n))\\ Altug Alkan, Sep 28 2015
    
  • PARI
    { A000459(n) = sum(m=0,n, sum(k=0,n-m, (-1)^k * binomial(n,k) * binomial(n-k,m) * 2^(2*k+m-n) * (2*n-2*m-k)! )); } \\ Max Alekseyev, Oct 06 2016

Formula

a(n) = A000316(n)/2^n.
a(n) = Sum_{k=0..n} Sum_{m=0..n-k} (-1)^k * n!/(k!*m!*(n-k-m)!) * 2^(2*k+m-n) * (2*n-2*m-k)!. - Max Alekseyev, Oct 06 2016
G.f.: Sum_{j=0..n*k} coeff(R(x, n, k), x, j)*(t-1)^j*(n*k-j)! where n is the number of kinds of cards, k is the number of cards of each kind (2 in this case) and coeff(R(x, n, k), x, j) is the coefficient of x^j of the rook polynomial R(x, n, k) = (k!^2*sum(x^j/((k-j)!^2*j!))^n (see Riordan or Stanley).
D-finite with recurrence a(n) = n*(2*n-1)*a(n-1)+2*n*(n-1)*a(n-2)-(2*n-1), a(1) = 0, a(2) = 1.
a(n) = round(2^(n/2 + 3/4)*Pi^(-1/2)*exp(-2)*n!*BesselK(1/2+n,2^(1/2))). - Mark van Hoeij, Oct 30 2011
(2*n+3)*a(n+3)=(2*n+5)^2*(n+2)*a(n+2)+(2*n+3)*(n+2)*a(n+1)-2*(2*n+5)*(n+1)*(n+2)*a(n). - Vaclav Kotesovec, Aug 31 2012
Asymptotic: a(n) ~ n^(2*n)*2^(n+1)*sqrt(Pi*n)/exp(2*n+2), Vaclav Kotesovec, Aug 31 2012
a(n) = (1/2^n)*A000316(n) = int_{0..inf} exp(-x)*(1/2*x^2 - 2*x + 1)^n dx. Asymptotic: a(n) ~ ((2*n)!/2^n)*exp(-2)*( 1 - 1/(2*n) - 23/(96*n^2) + O(1/n^3) ). See Nicolaescu. - Peter Bala, Jul 07 2014
Let S = x_1 + ... + x_n. a(n) equals the coefficient of (x_1*...*x_n)^2 in the expansion of product {i = 1..n} (S - x_i)^2 (MacMahon, Chapter III). - Peter Bala, Jul 08 2014
Conjecture: a(n+k) - a(n) is divisible by k. - Mark van Hoeij, Nov 15 2023

Extensions

More terms and edited by Barbara Haas Margolius (margolius(AT)math.csuohio.edu), Dec 22 2000
Edited by M. F. Hasler, Sep 27 2015
a(0)=1 prepended by Max Alekseyev, Oct 06 2016

A059073 Card-matching numbers (Dinner-Diner matching numbers).

Original entry on oeis.org

1, 0, 1, 56, 13833, 6699824, 5691917785, 7785547001784, 16086070907249329, 47799861987366600992, 196500286135805946117201, 1082973554682091552092493880, 7797122311868240909226166565881
Offset: 0

Views

Author

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

Keywords

Comments

A deck has n kinds of cards, 3 of each kind. The deck is shuffled and dealt in to n hands with 3 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)/((3n)!/3!^n).
Number of fixed-point-free permutations of n distinct letters (ABCD...), each of which appears thrice. If there is only one letter of each type we get A000166. - Zerinvary Lajos, Oct 15 2006
a(n) is the maximal number of totally mixed Nash equilibria in games of n players, each with 4 pure options. - Raimundas Vidunas, Jan 22 2014

Examples

			There are 56 ways of achieving zero matches when there are 3 cards of each kind and 3 kinds of card so a(3)=56.
		

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); seq(f(0,n,3)/3!^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, 3]/3!^n, {n, 0, 12}] (* Jean-François Alcover, May 21 2012, translated from Maple *)

Formula

G.f.: Sum_{j=0..n*k} coeff(R(x, n, k), x, j)*(t-1)^j*(n*k-j)! 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.

A059058 Card-matching numbers (Dinner-Diner matching numbers).

Original entry on oeis.org

1, 0, 0, 0, 1, 1, 0, 9, 0, 9, 0, 1, 56, 216, 378, 435, 324, 189, 54, 27, 0, 1, 13833, 49464, 84510, 90944, 69039, 38448, 16476, 5184, 1431, 216, 54, 0, 1, 6699824, 23123880, 38358540, 40563765, 30573900, 17399178, 7723640
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, 3 of each kind. The deck is shuffled and dealt in to n hands with 3 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..3n). The probability of exactly k matches is T(n,k)/((3n)!/(3!)^n).
Rows have lengths 1,4,7,10,...
Analogous to A008290 - Zerinvary Lajos, Jun 22 2005

Examples

			There are 9 ways of matching exactly 2 cards when there are 2 different kinds of cards, 3 of each in each of the two decks so T(2,2)=9.
		

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 6 do seq(coeff(f(t,n,3),t,m)/3!^n,m=0..3*n); od;
  • Mathematica
    p[x_, k_] := k!^2*Sum[ x^j/((k-j)!^2*j!), {j, 0, k}]; f[t_, n_, k_] := Sum[ Coefficient[ p[x, k]^n, x, j]*(t-1)^j*(n*k-j)!, {j, 0, n*k}]; Flatten[ Table[ Coefficient[ f[t, n, 3], t, m]/3!^n, {n, 0, 6}, {m, 0, 3n}]] (* Jean-François Alcover, Jan 31 2012, after 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 3) 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.

A000489 Card matching: Coefficients B[n,3] of t^3 in the reduced hit polynomial A[n,n,n](t).

Original entry on oeis.org

1, 16, 435, 7136, 99350, 1234032, 14219212, 155251840, 1628202762, 16550991200, 164111079110, 1594594348800, 15235525651840, 143518352447680, 1335670583147400, 12301278983461376, 112264111607438906, 1016361486936571680, 9136254276320346046
Offset: 1

Views

Author

Keywords

Comments

The definition uses notations of Riordan (1958), except for use of n instead of p. - M. F. Hasler, Sep 22 2015

References

  • J. Riordan, An Introduction to Combinatorial Analysis, Wiley, 1958, p. 193.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Programs

  • Magma
    [1, 16] cat [&+[3*Binomial(n, 3)*Binomial(n, k+3)*Binomial(n, k)*Binomial(n-3, k) + 6*n*Binomial(n, 2)*Binomial(n, k+1)*Binomial(n-1, k+2)*Binomial(n-2, k): k in [0..n-3]] + &+[n^3*Binomial(n-1, k)^3: k in [0..n-1]]: n in [3..20]]; // Vincenzo Librandi, Sep 22 2015
  • Mathematica
    a[n_] := 3*Binomial[n, 3]*Sum[Binomial[n, k + 3]*Binomial[n, k]*Binomial[n - 3, k], {k, 0, n - 3}] + 6 n*Binomial[n, 2]*Sum[Binomial[n, k + 1]*Binomial[n - 1, k + 2]*Binomial[n - 2, k], {k, 0, n - 3}] + n^3*Sum[Binomial[n - 1, k]^3, {k, 0, n - 1}]; Table[a[n], {n, 20}] (* T. D. Noe, Jun 20 2012 *)
  • PARI
    A000489(n)={3*binomial(n, 3)*sum(k=0,n-3,binomial(n, k+3)*binomial(n, k)*binomial(n-3, k))+6*n*binomial(n, 2)*sum(k=0,n-3,binomial(n, k+1)*binomial(n-1, k+2)*binomial(n-2, k))+n^3*sum(k=0,n-1,binomial(n-1, k)^3)} \\ M. F. Hasler, Sep 20 2015
    

Formula

a(n) = 3*binomial(n, 3)*sum(binomial(n, k+3)*binomial(n, k)*binomial(n-3, k), k=0..n-3) + 6n*binomial(n, 2)*sum(binomial(n, k+1)*binomial(n-1, k+2)*binomial(n-2, k), k=0..n-3) + n^3*sum(binomial(n-1, k)^3, k=0..n-1).
Recurrence: (n+3)*(243*n^7 - 1701*n^6 + 4239*n^5 - 4671*n^4 + 6042*n^3 - 17352*n^2 + 25032*n - 12016)*(n-1)^2*a(n) = n*(1701*n^9 - 6804*n^8 + 270*n^7 + 19116*n^6 + 35085*n^5 - 203640*n^4 + 324384*n^3 - 246736*n^2 + 75440*n - 5440)*a(n-1) + 8*n*(243*n^7 - 864*n^5 - 486*n^4 + 4233*n^3 - 5274*n^2 + 2460*n - 184)*(n-1)^2*a(n-2). - Vaclav Kotesovec, Aug 07 2013
a(n) ~ 3*sqrt(3)*n^2*8^(n-1)/Pi. - Vaclav Kotesovec, Aug 07 2013
a(n) = n^2*((27*n^3+54*n^2-57*n+8)*(n+2)*A001181(n)-(189*n^3+189*n^2-30*n+16)*(n-1)*A001181(n-1))/96. - Mark van Hoeij, Nov 14 2023

Extensions

More terms from Vladeta Jovovic, Apr 26 2000
More terms from Emeric Deutsch, Feb 19 2004
Definition made more precise by M. F. Hasler, Sep 22 2015

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.

A093772 a(n) is the smallest integer at which the value of the "truncated Mertens function" (= A088004) equals n.

Original entry on oeis.org

1, 6, 10, 14, 15, 21, 22, 26, 34, 35, 38, 39, 51, 55, 57, 58, 62, 65, 77, 85, 86, 87, 91, 93, 94, 95, 119, 122, 123, 129, 134, 142, 143, 145, 146, 158, 159, 161, 185, 202, 203, 205, 206, 209, 210, 213, 214, 215, 217, 218, 219, 221, 253, 254, 265, 278, 299, 301, 302
Offset: 1

Views

Author

Labos Elemer, Apr 28 2004

Keywords

Comments

Truncated Mertens function = summatory Moebius when argument runs through nonprimes.

Crossrefs

Programs

  • Mathematica
    mer[x_] :=mer[x]=mer[x-1]+MoebiusMu[x]; mer[0]=0;$RecursionLimit=1000; t=Table[mer[w]+PrimePi[w], {w, 1, 1000}] Table[Min[Flatten[Position[t, j]]], {j, 1, 200}]

A093773 a(n) is the smallest integer at which the value of the "truncated Mertens function" (= A088004) equals the n-th prime number.

Original entry on oeis.org

6, 10, 15, 22, 38, 51, 62, 77, 91, 123, 134, 159, 203, 206, 214, 253, 302, 305, 330, 341, 365, 395, 454, 489, 526, 542, 545, 554, 566, 586, 723, 753, 781, 794, 866, 870, 914, 933, 966, 1059, 1138, 1141, 1198, 1202, 1214, 1219, 1293, 1351, 1383, 1387, 1403
Offset: 1

Views

Author

Labos Elemer, Apr 28 2004

Keywords

Comments

Truncated Mertens function = summatory Moebius when argument runs through nonprimes. See A088004(n) = A002321(n) + A000720(n).

Crossrefs

Programs

  • Mathematica
    mer[x_] :=mer[x]=mer[x-1]+MoebiusMu[x]; mer[0]=0;$RecursionLimit=1000; t=Table[mer[w]+PrimePi[w], {w, 1, 1000}] Table[Min[Flatten[Position[t, Prime[j]]]], {j, 1, 200}]

Formula

a(n) = A093772(prime(n)) = A093772(A000040(n)). Solutions to min{x; A002321(x) + A000720(x) = A000040(n) = prime(n)} = a(n).

A059062 Card-matching numbers (Dinner-Diner matching numbers).

Original entry on oeis.org

1, 0, 0, 0, 0, 0, 1, 1, 0, 25, 0, 100, 0, 100, 0, 25, 0, 1, 2252, 15150, 48600, 99350, 144150, 156753, 131000, 87075, 45000, 19300, 6000, 1800, 250, 75, 0, 1, 44127009, 274314600, 822998550, 1583402400, 2189652825, 2311947008
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, 5 of each kind. The deck is shuffled and dealt in to n hands with 5 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..5n). The probability of exactly k matches is T(n,k)/((5n)!/(5!)^n).
Rows have lengths 1,6,11,16,...
Analogous to A008290 - Zerinvary Lajos, Jun 22 2005

Examples

			There are 25 ways of matching exactly 2 cards when there are 2 different kinds of cards, 5 of each so T(2,2)=25.
		

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 4 do seq(coeff(f(t,n,5),t,m)/5!^n,m=0..5*n); od;
  • Mathematica
    nmax = 4; r[x_, n_, k_] := (k!^2*Sum[ x^j/((k-j)!^2*j!), {j, 0, k}])^n; f[t_, n_, k_] := Sum[ Coefficient[ r[x, n, k], x, j]*(t-1)^j*(n*k-j)!, {j, 0, n*k}]; Flatten[ Table[ Coefficient[ f[t, n, 5], t, m]/5!^n, {n, 0, nmax}, {m, 0, 5n}]](* Jean-François Alcover, Nov 23 2011, after 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 5) 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.

A371252 Number of derangements of a multiset comprising n repeats of a 4-element set.

Original entry on oeis.org

1, 9, 297, 13833, 748521, 44127009, 2750141241, 178218782793, 11887871843817, 810822837267729, 56289612791763297, 3964402453931011233, 282558393168537751929, 20342533966643026042641, 1477174422125162468055897, 108064155440237168218117833, 7956914294959071176435002857
Offset: 0

Views

Author

Jeremy Tan, Mar 16 2024

Keywords

Comments

A deck has 4 suits of n cards each. The deck is shuffled and dealt into 4 hands of n cards each. A match occurs for every card in the i-th hand of suit i. a(n) is the number of ways of achieving no matches. The probability of no matches is a(n)/((4n)!/n!^4).

Examples

			There are a(13) = 20342533966643026042641 bridge deals where North, South, East and West are void in clubs, diamonds, hearts and spades, respectively.
		

Crossrefs

Column k=0 of A059068. The analogous sequence with 3 suits is A000172 and that with 2 suits is A000012.
Column k=4 of A372307.

Programs

  • Mathematica
    Table[Integrate[Exp[-x] LaguerreL[n, x]^4, {x, 0, Infinity}], {n, 0, 16}]
    (* or *)
    rec = n^3(2n-1)(5n-6)(10n-13) a[n] == (8300n^6-37350n^5+66698n^4-60393n^3+29297n^2-7263n+738) a[n-1] - (n-1)(16300n^5-81500n^4+151553n^3-123364n^2+39501n-4338) a[n-2] + 162(n-2)^3(n-1)(5n-1)(10n-3) a[n-3];
    RecurrenceTable[{rec, a[0] == 1, a[1] == 9, a[2] == 297}, a, {n, 0, 16}]
  • Python
    def A371252(n):
        l = [1, 9, 297]
        for k in range(3, n+1):
            m1 = (((((8300*k-37350)*k+66698)*k-60393)*k+29297)*k-7263)*k+738
            m2 = (k-1)*(((((16300*k-81500)*k+151553)*k-123364)*k+39501)*k-4338)
            m3 = 162*(k-2)**3*(k-1)*(5*k-1)*(10*k-3)
            r = (m1*l[-1] - m2*l[-2] + m3*l[-3]) // (k**3*(2*k-1)*(5*k-6)*(10*k-13))
            l.append(r)
        return l[n]

Formula

a(n) = Integral_{x=0..oo} exp(-x)*L_n(x)^4 dx, where L_n(x) is the Laguerre polynomial of degree n (Even and Gillis).
D-finite with recurrence n^3*(2*n-1)*(5*n-6)*(10*n-13)*a(n) = (8300*n^6 - 37350*n^5 + 66698*n^4 - 60393*n^3 + 29297*n^2 - 7263*n + 738)*a(n-1) - (n-1)*(16300*n^5 - 81500*n^4 + 151553*n^3 - 123364*n^2 + 39501*n - 4338)*a(n-2) + 162*(n-2)^3*(n-1)*(5*n-1)*(10*n-3)*a(n-3) (Ekhad).
a(n) = [(w*x*y*z)^n] ((x+y+z)*(w+y+z)*(w+x+z)*(w+x+y))^n.
a(n) ~ 3^(4*n + 3) / (32 * Pi^(3/2) * n^(3/2)). - Vaclav Kotesovec, Mar 29 2024
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