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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A079639 Matrix product of Stirling1-triangle A008275(n,k) and unsigned Lah-triangle |A008297(n,k)|.

Original entry on oeis.org

1, 1, 1, 2, 3, 1, 4, 11, 6, 1, 14, 40, 35, 10, 1, 38, 184, 195, 85, 15, 1, 216, 840, 1204, 665, 175, 21, 1, 600, 4920, 7616, 5369, 1820, 322, 28, 1, 6240, 26616, 54116, 44016, 18669, 4284, 546, 36, 1, 9552, 197856, 392460, 383480, 191205, 54453, 9030, 870, 45, 1, 319296, 1177176, 3229776, 3449600, 2017070, 679371, 139293, 17490, 1320, 55, 1, -519312
Offset: 1

Views

Author

Vladeta Jovovic, Jan 30 2003

Keywords

Comments

Also the Bell transform of A006252(n+1). For the definition of the Bell transform see A264428. - Peter Luschny, Jan 26 2016

Crossrefs

Cf. A006252 (first column).

Programs

  • Maple
    # The function BellMatrix is defined in A264428.
    # Adds (1, 0, 0, 0, ..) as column 0.
    BellMatrix(n -> add(k!*combinat:-stirling1(n+1,k),k=0..n+1),9); # Peter Luschny, Jan 26 2016
  • Mathematica
    BellMatrix[f_, len_] := With[{t = Array[f, len, 0]}, Table[BellY[n, k, t], {n, 0, len - 1}, {k, 0, len - 1}]];
    rows = 12;
    B = BellMatrix[Function[n, Sum[k!*StirlingS1[n+1, k], {k, 0, n+1}]], rows];
    Table[B[[n, k]], {n, 2, rows}, {k, 2, n}] // Flatten (* Jean-François Alcover, Jun 27 2018, after Peter Luschny *)

Formula

T(n, k) = Sum_{i=k..n} A008275(n, i) * |A008297(i, k)|.
E.g.f: (1+x)^(y/(1-log(1+x))). - Vladeta Jovovic, Nov 22 2003

A088729 Matrix product of Stirling2-triangle A008277(n,k) and unsigned Lah-triangle |A008297(n,k)|.

Original entry on oeis.org

1, 3, 1, 13, 9, 1, 75, 79, 18, 1, 541, 765, 265, 30, 1, 4683, 8311, 3870, 665, 45, 1, 47293, 100989, 59101, 13650, 1400, 63, 1, 545835, 1362439, 960498, 278901, 38430, 2618, 84, 1, 7087261, 20246445, 16700545, 5844510, 1012431, 92610, 4494, 108, 1
Offset: 1

Views

Author

Vladeta Jovovic, Nov 22 2003

Keywords

Comments

Also the Bell transform of A000670(n+1). For the definition of the Bell transform see A264428. - Peter Luschny, Jan 26 2016
Also the number of k-dimensional flats of the n-dimensional Catalan arrangement. - Shuhei Tsujie, May 05 2019

Crossrefs

Cf. A000670(first column), A075729(row sums).

Programs

  • Maple
    # The function BellMatrix is defined in A264428.
    # Adds (1, 0, 0, 0, ..) as column 0.
    BellMatrix(n -> add(combinat:-eulerian1(n+1, k)*2^k, k=0..n+1), 9); # Peter Luschny, Jan 26 2016
  • Mathematica
    BellMatrix[f_, len_] := With[{t = Array[f, len, 0]}, Table[BellY[n, k, t], {n, 0, len - 1}, {k, 0, len - 1}]];
    rows = 12;
    B = BellMatrix[Function[n, HurwitzLerchPhi[1/2, -n-1, 0]/2], rows];
    Table[B[[n, k]], {n, 2, rows}, {k, 2, n}] // Flatten (* Jean-François Alcover, Jun 27 2018, after Peter Luschny *)

Formula

E.g.f.: exp((exp(x)-1)*y/(2-exp(x))).

A088814 Matrix product of unsigned Lah-triangle |A008297(n,k)| and Stirling2-triangle A008277(n,k).

Original entry on oeis.org

1, 3, 1, 13, 9, 1, 73, 79, 18, 1, 501, 755, 265, 30, 1, 4051, 7981, 3840, 665, 45, 1, 37633, 93135, 57631, 13580, 1400, 63, 1, 394353, 1192591, 911582, 274141, 38290, 2618, 84, 1, 4596553, 16645431, 15285313, 5633922, 999831, 92358, 4494, 108, 1, 58941091
Offset: 1

Views

Author

Vladeta Jovovic, Nov 22 2003

Keywords

Comments

Also the Bell transform of A000262(n+1). For the definition of the Bell transform see A264428. - Peter Luschny, Jan 26 2016

Crossrefs

Cf. A000262(first column), A084357(row sums).

Programs

  • Maple
    # The function BellMatrix is defined in A264428.
    # Adds (1, 0, 0, 0, ..) as column 0.
    BellMatrix(n -> simplify(hypergeom([-n,-n-1],[],1)), 9); # Peter Luschny, Jan 26 2016
  • Mathematica
    BellMatrix[f_, len_] := With[{t = Array[f, len, 0]}, Table[BellY[n, k, t], {n, 0, len - 1}, {k, 0, len - 1}]];
    rows = 12;
    B = BellMatrix[Function[n, Sum[BellY[n+1, k, Range[n+1]!], {k, 0, n+1}]], rows];
    Table[B[[n, k]], {n, 2, rows}, {k, 2, n}] // Flatten (* Jean-François Alcover, Jun 28 2018, after Peter Luschny_ *)

Formula

E.g.f.: exp(y*(exp(x/(1-x))-1)).

A169653 Triangle T(n,k) = A008297(n,k) + A008297(n,n-k+1), read by rows.

Original entry on oeis.org

-2, 3, 3, -7, -12, -7, 25, 48, 48, 25, -121, -260, -240, -260, -121, 721, 1830, 1500, 1500, 1830, 721, -5041, -15162, -13230, -8400, -13230, -15162, -5041, 40321, 141176, 142296, 70560, 70560, 142296, 141176, 40321, -362881, -1451592, -1695456, -874944, -423360, -874944, -1695456, -1451592, -362881
Offset: 1

Views

Author

Roger L. Bagula, Apr 05 2010

Keywords

Examples

			Triangle begins as:
     -2;
      3,      3;
     -7,    -12,     -7;
     25,     48,     48,    25;
   -121,   -260,   -240,  -260,   -121;
    721,   1830,   1500,  1500,   1830,    721;
  -5041, -15162, -13230, -8400, -13230, -15162,  -5041;
  40321, 141176, 142296, 70560,  70560, 142296, 141176, 40321;
		

Crossrefs

Programs

  • Magma
    A001263:= func< n,k | Binomial(n-1, k-1)*Binomial(n,k-1)/k >;
    A169653:= func< n,k | (-1)^n*A001263(n, k)*(Factorial(k) + Factorial(n-k+1)) >;
    [A169653(n, k): k in [1..n], n in [1..10]]; // G. C. Greubel, Feb 23 2021
  • Mathematica
    t[n_, m_] = (-1)^n*(n!/m!)*Binomial[n-1, m-1];
    T[n_, m_] = t[n, m] + t[n, n-m+1];
    Table[T[n,k], {n,12}, {k,n}]//Flatten (* modified by G. C. Greubel, Feb 23 2021 *)
  • Sage
    def A001263(n, k): return binomial(n-1, k-1)*binomial(n,k-1)/k
    def A169653(n, k): return (-1)^n*A001263(n, k)*(factorial(k) + factorial(n-k+1))
    flatten([[A169653(n,k) for k in (1..n)] for n in (1..10)]) # G. C. Greubel, Feb 23 2021
    

Formula

T(n, k) = t(n, k) + t(n, n-k+1), where t(n, k) = (-1)^n*(n!/k!)*binomial(n-1, k-1).
T(n, k) = A008297(n,k) + A008297(n,n-k+1).
From G. C. Greubel, Feb 23 2021: (Start)
T(n, k) = (-1)^n * (A105278(n, k) + A105278(n, n-k+1)).
T(n, k) = (-1)^n * ( k! + (n-k+1)! ) * A001263(n, k).
Sum_{k=1..n} T(n, k) = 2 * (-1)^n * A000262(n). (End)

Extensions

Edited by G. C. Greubel, Feb 23 2021

A079005 Exponential transform of unsigned Lah-triangle |A008297(n,k)|.

Original entry on oeis.org

1, 2, 2, 6, 12, 5, 24, 72, 60, 15, 120, 480, 600, 300, 52, 720, 3600, 6000, 4500, 1560, 203, 5040, 30240, 63000, 63000, 32760, 8526, 877, 40320, 282240, 705600, 882000, 611520, 238728, 49112, 4140, 362880, 2903040, 8467200, 12700800, 11007360
Offset: 1

Views

Author

Vladeta Jovovic, Feb 01 2003

Keywords

Examples

			1; 2,2; 6,12,5; 24,72,60,15; 120,480,600,300,52; ...
		

Crossrefs

Formula

E.g.f.: exp(exp(x*y/(1-x))-1). a(n, k) = n!/k! * binomial(n-1, k-1) * bell(k) = |A008297(n, k)| * A000110(k).

A079621 Matrix square of unsigned Lah triangle abs(A008297(n,k)) or A105278(n,k).

Original entry on oeis.org

1, 4, 1, 24, 12, 1, 192, 144, 24, 1, 1920, 1920, 480, 40, 1, 23040, 28800, 9600, 1200, 60, 1, 322560, 483840, 201600, 33600, 2520, 84, 1, 5160960, 9031680, 4515840, 940800, 94080, 4704, 112, 1, 92897280, 185794560, 108380160, 27095040, 3386880, 225792
Offset: 1

Views

Author

Vladeta Jovovic, Jan 29 2003

Keywords

Comments

Also the Bell transform of A002866(n+1). For the definition of the Bell transform see A264428. - Peter Luschny, Jan 26 2016
Also the number of k-dimensional flats of the extended Shi arrangement of dimension n consisting of hyperplanes x_i - x_j = d (1 <= i < j <= n, -1 <= d <= 2). - Shuhei Tsujie, Apr 26 2019

Examples

			Triangle begins:
     1;
     4,    1;
    24,   12,   1;
   192,  144,  24,  1;
  1920, 1920, 480, 40, 1;
  ...
		

Crossrefs

Cf. A002866 (first column), A025168 (row sums).

Programs

  • Maple
    # The function BellMatrix is defined in A264428.
    # Adds (1, 0, 0, 0, ..) as column 0.
    BellMatrix(n -> 2^n*(n+1)!, 9); # Peter Luschny, Jan 26 2016
  • Mathematica
    BellMatrix[f_, len_] := With[{t = Array[f, len, 0]}, Table[BellY[n, k, t], {n, 0, len - 1}, {k, 0, len - 1}]];
    B = BellMatrix[2^#*(#+1)!&, rows = 12];
    Table[B[[n, k]], {n, 2, rows}, {k, 2, n}] // Flatten (* Jean-François Alcover, Jun 28 2018, after Peter Luschny *)

Formula

E.g.f.: exp(x*y/(1-2*x)).
T(n, k) = n!/k!*binomial(n-1, k-1)*2^(n-k). - Vladeta Jovovic, Sep 24 2003
The n-th row polynomial equals x o (x + 2) o (x + 4) o ... o (x + 2*n), where o is the deformed Hadamard product of power series defined in Bala, section 3.1. - Peter Bala, Jan 18 2018

A156786 The triangular sequence of symmetrical Lah numbers (A111596, A008297) : L(n, m) = (-1)^n* binomial(n,k)*binomial(n-1, k-1)*( (n-k)! + (n-k)*(k-1)! ), with L(0,0) = 2, L(n,0) = L(n,n) = (-1)^n.

Original entry on oeis.org

2, -1, -1, 1, 4, 1, -1, -12, -12, -1, 1, 36, 72, 36, 1, -1, -140, -360, -360, -140, -1, 1, 750, 2100, 2400, 2100, 750, 1, -1, -5082, -15750, -16800, -16800, -15750, -5082, -1, 1, 40376, 142296, 152880, 117600, 152880, 142296, 40376, 1, -1, -362952, -1453536
Offset: 0

Views

Author

Roger L. Bagula, Feb 15 2009

Keywords

Comments

Row sums are: {2, -2, 6, -26, 146, -1002, 8102, -75266, 788706, -9193106, 117882182, ...} = signed version of 2*A000262.

Examples

			Triangle begins as:
   2;
  -1,    -1;
   1,     4,      1;
  -1,   -12,    -12,     -1;
   1,    36,     72,     36,      1;
  -1,  -140,   -360,   -360,   -140,     -1;
   1,   750,   2100,   2400,   2100,    750,      1;
  -1, -5082, -15750, -16800, -16800, -15750,  -5082,    -1;
   1, 40376, 142296, 152880, 117600, 152880, 142296, 40376, 1;
		

References

  • J. Riordan, Combinatorial Identities, Wiley, 1968, p.48

Crossrefs

Programs

  • Magma
    [[n eq 0 and k eq 0 select 2 else k eq 0 or k eq n select (-1)^n else (-1)^n*Binomial(n,k)*Binomial(n-1, k-1)*( Factorial(n-k) + (n-k)* Factorial(k-1) ): k in [0..n]]: n in [0..10]]; // G. C. Greubel, May 20 2019
    
  • Mathematica
    L[n_, k_]:= If[n==0 && k==0, 2, If[k==0 || k==n, (-1)^n, (-1)^n* Binomial[n,k]*Binomial[n-1,k-1]*( (n-k)! + (n-k)*(k-1)! )]]; Table[L[n, k], {n, 0, 10}, {k, 0, n}]//Flatten
  • PARI
    { L(n, k) = if(n==0 && k==0, 2, if(k==0 || k==n, (-1)^n, (-1)^n* binomial(n,k)*binomial(n-1, k-1)*( (n-k)! + (n-k)*(k-1)! ) )) }; \\ G. C. Greubel, May 20 2019
    
  • Sage
    def L(n, k):
        if (k==0 and n==0): return 2
        elif (k==0 or k==n): return (-1)^n
        else: return (-1)^n*binomial(n,k)*binomial(n-1, k-1)*( factorial(n-k) + (n-k)*factorial(k-1) )
    [[L(n, k) for k in (0..n)] for n in (0..10)] # G. C. Greubel, May 20 2019

Formula

L(n, m) = if m = 0 then KroneckerDelta(n, 0) otherwise (-1)^n*(n!/m!)* binomial(n-1, m-1) + if m = n then KroneckerDelta(n, 0) otherwise (-1)^n* n! *binomial(n,m)* binomial(n-1, n-m-1).
L(n, m) = (-1)^n* binomial(n,k)*binomial(n-1, k-1)*( (n-k)! + (n-k)*(k-1)! ), with L(0,0) = 2, L(n,0) = L(n,n) = (-1)^n. - G. C. Greubel, May 20 2019

Extensions

Edited by G. C. Greubel, May 20 2019

A223512 Triangle T(n,k) represents the coefficients of (x^10*d/dx)^n, where n=1,2,3,...;generalization of Stirling numbers of second kind A008277, Lah-numbers A008297.

Original entry on oeis.org

1, 10, 1, 190, 30, 1, 5320, 1060, 60, 1, 196840, 45600, 3400, 100, 1, 9054640, 2340040, 208800, 8300, 150, 1, 498005200, 140096880, 14241640, 690200, 17150, 210, 1, 31872332800, 9604302400, 1080045120, 60485040, 1856400, 31640, 280, 1, 2326680294400
Offset: 1

Views

Author

Udita Katugampola, Mar 23 2013

Keywords

Examples

			1;
10,1;
190,30,1;
5320,1060,60,1;
196840,45600,3400,100,1;
9054640,2340040,208800,8300,150,1;
498005200,140096880,14241640,690200,17150,210,1;
31872332800,9604302400,1080045120,60485040,1856400,31640,280,1,2326680294400
		

Crossrefs

Programs

  • Maple
    b[0]:=g(x):
    for j from 1 to 10 do
    b[j]:=simplify(x^10*diff(b[j-1],x$1);
    end do;

A223514 Triangle T(n,k) represents the coefficients of (x^12*d/dx)^n, where n=1,2,3,...; generalization of Stirling numbers of second kind A008277, Lah-numbers A008297.

Original entry on oeis.org

1, 12, 1, 276, 36, 1, 9384, 1536, 72, 1, 422280, 80040, 4920, 120, 1, 23647680, 4984560, 365400, 12000, 180, 1, 1584394560, 362597760, 30197160, 1205400, 24780, 252, 1, 123582775680, 30229617600, 2778370560, 127834560, 3237360, 45696, 336, 1, 1099867035520
Offset: 1

Views

Author

Udita Katugampola, Mar 23 2013

Keywords

Examples

			1;
12,1;
276,36,1;
9384,1536,72,1;
422280,80040,4920,120,1;
23647680,4984560,365400,12000,180,1;
1584394560,362597760,30197160,1205400,24780,252,1;
123582775680,30229617600,2778370560,127834560,3237360,45696,336,1;
1099867035520,...
		

Crossrefs

Programs

  • Maple
    b[0]:=f(x):
    for j from 1 to 10 do
    b[j]:=simplify(x^12*diff(b[j-1],x$1);
    end do;

A223515 Triangle T(n,k) represents the coefficients of (x^13*d/dx)^n, where n=1,2,3,...; generalization of Stirling numbers of second kind A008277, Lah-numbers A008297.

Original entry on oeis.org

1, 13, 1, 325, 39, 1, 12025, 1807, 78, 1, 589225, 102375, 5785, 130, 1, 35942725, 6936475, 466830, 14105, 195, 1, 2623818925, 549241875, 41948725, 1538810, 29120, 273, 1, 223024608625, 49858620175, 4198780950, 177364005, 4130490, 53690, 364, 1, 21633387036625
Offset: 1

Views

Author

Udita Katugampola, Mar 23 2013

Keywords

Examples

			1;
13,1;
325,39,1;
12025,1807,78,1;
589225,102375,5785,130,1;
35942725,6936475,466830,14105,195,1
2623818925,549241875,41948725,1538810,29120,273,1;
223024608625,49858620175,4198780950,177364005,4130490,53690,364,1;
21633387036625,...
		

Crossrefs

Programs

  • Maple
    b[0]:=f(x):
    for j from 1 to 10 do
    b[j]:=simplify(x^13*diff(b[j-1],x$1);
    end do;
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