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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A066912 Fourth column of the Eulerian triangle A008292 in square array format.

Original entry on oeis.org

0, 1, 26, 302, 2416, 15619, 88234, 455192, 2203488, 10187685, 45533450, 198410786, 848090912, 3572085255, 14875399450, 61403313100, 251732291184, 1026509354985, 4168403181210, 16871482830550, 68111623139600
Offset: 0

Views

Author

Randall L Rathbun, Jan 22 2002

Keywords

Crossrefs

Essentially the same as A000498.

Programs

  • PARI
    a(n)=4^(n+3)-(n+4)*3^(n+3)+1/2*(n+3)*(n+4)*2^(n+3)-1/6*(n+2)*(n+3)*(n+4)

Formula

a(n) = 4^(n+3) - (n+4)*3^(n+3) + (1/2)*(n+3)*(n+4)*2^(n+3) - (1/6)*(n+2)*(n+3)*(n+4).

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), Jun 11 2002

A089249 Triangular array read by rows illustrating the connection between A000522 and A008292.

Original entry on oeis.org

1, 3, 4, 6, 16, 11, 10, 40, 55, 26, 15, 80, 165, 156, 57, 21, 140, 385, 546, 399, 120
Offset: 1

Views

Author

Alford Arnold, Dec 11 2003

Keywords

Comments

The general case corresponding to other diagonals of A046802 can be derived from A046802(m,n) = Sum C(m-1,n-1) * A008292(m-r,n-1).

Examples

			The fifth row of the array is 15 80 165 156 57 resulting from A089249 (1 4 11 26 57 ) times ( 15 20 15 6 1)
		

Crossrefs

Row sums = the third diagonal of A046802.

A125108 Column sums of a Gaussian polynomial-shaped array. Row sums generate the Eulerian array A008292.

Original entry on oeis.org

1, 2, 4, 10, 26, 72, 202, 580
Offset: 1

Views

Author

Alford Arnold, Dec 25 2006

Keywords

Comments

Column sums of the Gaussian polynomial template count numeric partitions. Row sums of the Gaussian polynomial template generate Pascal's triangle. A105552 has the same shape as the template and counts compositions. Row sums of the Eulerian array counts permutations of n object.

Examples

			The column sums begin 1 2 4 10 26 72 202 580 ... because the structure of the Array begin as follows:
1..................................................................
......1............................................................
......1............................................................
............1......................................................
............2......2...............................................
............1......................................................
..................1................................................
..................3......5......3..................................
..................3......5......3..................................
..................1................................................
............................1......................................
............................4.......9.......9.......4..............
............................6.......16......22......16.......6.....
............................4.......9.......9.......4..............
............................1......................................
etc.
		

Crossrefs

A147563 Irregular triangle, T(n, k) = [x^k] p(n, x), where p(n, x) = 4*Sum_{j=0..n} A008292(n+1, j) * (x/2)^j * (1-x/2)^(n-j), read by rows.

Original entry on oeis.org

4, 4, 4, 4, -2, 4, 16, -8, 4, 44, -6, -16, 4, 4, 104, 84, -136, 34, 4, 228, 606, -584, -24, 102, -17, 4, 480, 2832, -1088, -2208, 1488, -248, 4, 988, 11122, 5536, -20840, 8896, 832, -992, 124, 4, 2008, 39772, 74296, -118190, -2144, 51952, -22112, 2764
Offset: 0

Views

Author

Roger L. Bagula, Nov 07 2008

Keywords

Examples

			Irregular triangle begins as:
  4;
  4;
  4,    4,    -2;
  4,   16,    -8;
  4,   44,    -6,   -16,       4;
  4,  104,    84,  -136,      34;
  4,  228,   606,  -584,     -24,   102,   -17;
  4,  480,  2832, -1088,   -2208,  1488,  -248;
  4,  988, 11122,  5536,  -20840,  8896,   832,   -992,  124;
  4, 2008, 39772, 74296, -118190, -2144, 51952, -22112, 2764;
		

Crossrefs

Cf. A008292.

Programs

  • Magma
    A008292:= func< n,k | (&+[(-1)^j*Binomial(n+1, j)*(k-j)^n: j in [0..k]]) >;
    T:= func< n,k | (-1/2)^(k-2)*(&+[(-1)^j*Binomial(n-j,k-j)*A008292(n+1,j+1): j in [0..k]]) >;
    [Floor(T(n,k)): k in [0..2*Floor(n/2)], n in [0..16]]; // G. C. Greubel, Oct 27 2022; Mar 03 2023
    
  • Mathematica
    (* First program *)
    nmax:= 15;
    p[x_, n_]= (1-x)^(n+1)*PolyLog[-n, x]/x;
    b= Table[CoefficientList[p[x, n], x], {n, nmax+1}];
    F[n_]:= CoefficientList[4*Sum[b[[n+1]][[m+1]]*(x/2)^(n-m)*(1-x/2)^m, {m, 0, n}], x];
    T[n_]:= If[IntegerQ[F[n]], F[n], Sign[F[n]]*Abs[Round[F[n] - 1/2]]];
    Table[T[n], {n, 0, nmax}]//Flatten
    (* Second program *)
    A008292[n_, k_]:= Sum[(-1)^j*(k-j)^n*Binomial[n+1,j], {j,0,k}];
    F[n_, k_]:= (-1/2)^(k-2)*Sum[(-1)^j*Binomial[n-j, k-j]*A008292[n+1, j+ 1], {j,0,k}];
    T[n_, k_]:= If[IntegerQ[F[n,k]], F[n,k], Sign[F[n,k]]*Abs[Round[F[n, k] - 1/2]]];
    Table[T[n, k], {n,0,16}, {k, 0, 2*Floor[n/2]}]//Flatten (* G. C. Greubel, Mar 03 2023 *)
  • SageMath
    def A008292(n,k): return sum( (-1)^j*binomial(n+1, j)*(k-j)^n for j in range(k+1) )
    def A147563(n,k): return floor((-1/2)^(k-2)*sum((-1)^j*binomial(n-j, k-j)*A008292(n+1,j+1) for j in range(k+1)))
    flatten([[A147563(n,k) for k in range(2*floor(n/2) + 1)] for n in range(16)]) # G. C. Greubel, Oct 27 2022; Mar 03 2023

Formula

T(n, k) = coefficients [x^k]( p(n, x) ), where p(n, x) = 4*Sum_{j=0..n} A008292(n+1, j) * (x/2)^j * (1-x/2)^(n-j).
T(n, k) = round( (-1/2)^(k-2) * Sum_{j=0..k} (-1)^j*binomial(n-j, k-j) * A008292(n+1, j+1) ). - G. C. Greubel, Mar 03 2023

Extensions

Edited by G. C. Greubel, Oct 27 2022

A174303 A symmetrical triangle: T(n,k) = A008292(n+1, k) * f(n,k), where f(n,k) = 2^k when floor(n/2) >= k, otherwise 2^(n-k).

Original entry on oeis.org

1, 1, 1, 1, 8, 1, 1, 22, 22, 1, 1, 52, 264, 52, 1, 1, 114, 1208, 1208, 114, 1, 1, 240, 4764, 19328, 4764, 240, 1, 1, 494, 17172, 124952, 124952, 17172, 494, 1, 1, 1004, 58432, 705872, 2499040, 705872, 58432, 1004, 1, 1, 2026, 191360, 3641536, 20965664, 20965664, 3641536, 191360, 2026, 1
Offset: 0

Views

Author

Roger L. Bagula, Mar 15 2010

Keywords

Comments

Row sums are: {1, 2, 10, 46, 370, 2646, 29338, 285238, 4029658, ...}.

Examples

			Triangle begins as:
  1;
  1,    1;
  1,    8,     1;
  1,   22,    22,      1;
  1,   52,   264,     52,       1;
  1,  114,  1208,   1208,     114,      1;
  1,  240,  4764,  19328,    4764,    240,     1;
  1,  494, 17172, 124952,  124952,  17172,   494,    1;
  1, 1004, 58432, 705872, 2499040, 705872, 58432, 1004,   1;
		

Crossrefs

Programs

  • Magma
    Eulerian:= func< n,k | (&+[(-1)^j*Binomial(n+1,j)*(k-j+1)^n: j in [0..k+1]]) >; [[Floor(n/2) ge k select 2^k*Eulerian(n+1,k) else 2^(n-k)*Eulerian(n+1,k): k in [0..n]]: n in [0..10]]; // G. C. Greubel, Apr 15 2019
    
  • Mathematica
    Eulerian[n_, k_]:= Sum[(-1)^j*Binomial[n+1,j]*(k-j+1)^n, {j,0,k+1}];
    Table[Eulerian[n+1,m]*If[Floor[n/2] >= m, 2^m, 2^(n-m)], {n,0,10}, {m,0,n} ]//Flatten (* modified by G. C. Greubel, Apr 15 2019 *)
  • PARI
    {eulerian(n,k) = sum(j=0,k+1, (-1)^j*binomial(n+1,j)*(k-j+1)^n)};
    for(n=0,10, for(k=0,n, print1(eulerian(n+1,k)*if(floor(n/2)>=k, 2^k, 2^(n-k)), ", "))) \\ G. C. Greubel, Apr 15 2019
    
  • Sage
    def Eulerian(n,k): return sum((-1)^j*binomial(n+1,j)*(k-j+1)^n for j in (0..k+1))
    def T(n,k):
       if floor(n/2)>=k: return 2^k*Eulerian(n+1,k)
       else: return 2^(n-k)*Eulerian(n+1,k)
    [[T(n,k) for k in (0..n)] for n in (0..10)] # G. C. Greubel, Apr 15 2019

Formula

T(n,k) = Eulerian(n+1, k)*if(floor(n/2) greater than or equal to k then 2^m otherwise 2^(n-k)), where the Eulerian numbers are defined as A008292(n,k).

Extensions

Edited by G. C. Greubel, Apr 15 2019

A176204 Triangle T(n, k) = 4 * A008292(n+1, k) - 3, read by rows.

Original entry on oeis.org

1, 1, 1, 1, 13, 1, 1, 41, 41, 1, 1, 101, 261, 101, 1, 1, 225, 1205, 1205, 225, 1, 1, 477, 4761, 9661, 4761, 477, 1, 1, 985, 17169, 62473, 62473, 17169, 985, 1, 1, 2005, 58429, 352933, 624757, 352933, 58429, 2005, 1, 1, 4049, 191357, 1820765, 5241413, 5241413, 1820765, 191357, 4049, 1
Offset: 0

Views

Author

Roger L. Bagula, Apr 11 2010

Keywords

Comments

This sequence belongs to the class defined by T(n, m, q) = 2*T(n, m, q-1) - 1. The first few q values gives the sequences: A008292(n+1, k) (q=0), A176200 (q=1), this sequence (q=2).
Row sums are: {1, 2, 15, 84, 465, 2862, 20139, 161256, 1451493, 14515170, 159667167, ...}.
Former title: A recursive symmetrical triangular sequence based on Eulerian numbers: q=2: T(n, m, q) = 2*T(n, m, q-1) - 1.

Examples

			Triangle begins as:
  1;
  1,    1;
  1,   13,      1;
  1,   41,     41,       1;
  1,  101,    261,     101,       1;
  1,  225,   1205,    1205,     225,       1;
  1,  477,   4761,    9661,    4761,     477,       1;
  1,  985,  17169,   62473,   62473,   17169,     985,      1;
  1, 2005,  58429,  352933,  624757,  352933,   58429,   2005,    1;
  1, 4049, 191357, 1820765, 5241413, 5241413, 1820765, 191357, 4049, 1;
		

Crossrefs

Programs

  • Magma
    Eulerian:= func< n,k | (&+[(-1)^j*Binomial(n+1,j)*(k-j+1)^n: j in [0..k+1]]) >;
    [[4*Eulerian(n+1,k) -3: k in [0..n]]: n in [0..12]]; // G. C. Greubel, Mar 12 2020
    
  • Maple
    A008292:= (n,k) -> add((-1)^j*binomial(n+1,j)*(k-j+1)^n, j=0..k+1);
    A176204:= (n,k,q) -> 2^q*( A008292(n+1,k) -1) + 1;
    seq(seq( A176204(n,k,2), k=0..n), n=0..12); # G. C. Greubel, Mar 12 2020
  • Mathematica
    Eulerian[n_, k_]:= Sum[(-1)^j*Binomial[n+1, j]*(k-j+1)^n, {j,0,k+1}];
    T[n_, m_, q_]:= 2^q*Eulerian[n+1, m] - 2^q +1;
    Table[T[n, m, 2], {n,0,12}, {m,0,n}]//Flatten (* modified by G. C. Greubel, Mar 12 2020 *)
  • PARI
    Eulerian(n,k) = sum(j=0,k+1, (-1)^j*binomial(n+1,j)*(k-j+1)^n);
    T(n,k,q) = 2^q*Eulerian(n+1,k) - (2^q - 1); \\ G. C. Greubel, Mar 12 2020
    
  • Sage
    def Eulerian(n,k): return sum((-1)^j*binomial(n+1,j)*(k-j+1)^n for j in (0..k+1))
    def T(n,k,q): return 2^q*Eulerian(n+1,k) - 2^q + 1
    [[T(n,k,2) for k in (0..n)] for n in (0..12)] # G. C. Greubel, Mar 12 2020

Formula

T(n, m, q) = 2*T(n, m, q-1) - 1, with T(n, m, 0) = A008292(n+1, m).
From G. C. Greubel, Mar 12 2020: (Start)
T(n, k, q) = 2^q * A008292(n+1, k) - (2^q - 1).
Sum_{k=0..n} T(n, k, q) = (n+1)*( 2^q * n! - 2^q + 1) (row sums). (End)

Extensions

Edited by G. C. Greubel, Mar 12 2020

A176492 Triangle T(n,k) = A176492(n,k) + A008292(n+1,k+1) - 1 read along rows 0<=k<=n.

Original entry on oeis.org

1, 1, 1, 1, 13, 1, 1, 45, 45, 1, 1, 129, 365, 129, 1, 1, 353, 2293, 2293, 353, 1, 1, 965, 12937, 28397, 12937, 965, 1, 1, 2677, 69261, 290993, 290993, 69261, 2677, 1, 1, 7561, 360853, 2661809, 4987461, 2661809, 360853, 7561, 1, 1, 21705, 1852053, 22618437
Offset: 0

Views

Author

Roger L. Bagula, Apr 19 2010

Keywords

Comments

Row sums are 1, 2, 15, 92, 625, 5294, 56203, 725864, 11047909, 193052642, 3795725791,....

Examples

			1;
1, 1;
1, 13, 1;
1, 45, 45, 1;
1, 129, 365, 129, 1;
1, 353, 2293, 2293, 353, 1;
1, 965, 12937, 28397, 12937, 965, 1;
1, 2677, 69261, 290993, 290993, 69261, 2677, 1;
1, 7561, 360853, 2661809, 4987461, 2661809, 360853, 7561, 1;
, 21705, 1852053, 22618437, 72034125, 72034125, 22618437, 1852053, 21705, 1;
1, 63117, 9421457, 182707997, 926399717, 1558541213, 926399717, 182707997, 9421457, 63117, 1;
		

Crossrefs

Programs

  • Maple
    A176492 := proc(n,k)
        A176491(n,k)+A008292(n+1,k+1)-1 ;
    end proc: # R. J. Mathar, Jun 16 2015
  • Mathematica
    (*A060187*)
    p[x_, n_] = (1 - x)^(n + 1)*Sum[(2*k + 1)^n*x^k, {k, 0, Infinity}];
    f[n_, m_] := CoefficientList[FullSimplify[ExpandAll[p[x, n]]], x][[m + 1]];
    << DiscreteMath`Combinatorica`;
    t[n_, m_, 0] := Binomial[n, m];
    t[n_, m_, 1] := Eulerian[1 + n, m];
    t[n_, m_, 2] := f[n, m];
    t[n_, m_, q_] := t[n, m, q] = t[n, m, q - 2] + t[n, m, q - 3] - 1;
    Table[Flatten[Table[Table[t[n, m, q], {m, 0, n}], {n, 0, 10}]], {q, 0, 10}]

A177823 Triangle of Eulerian numbers squared: A008292(n,m)^2 read by rows.

Original entry on oeis.org

1, 1, 1, 1, 16, 1, 1, 121, 121, 1, 1, 676, 4356, 676, 1, 1, 3249, 91204, 91204, 3249, 1, 1, 14400, 1418481, 5837056, 1418481, 14400, 1, 1, 61009, 18429849, 243953161, 243953161, 18429849, 61009, 1, 1, 252004, 213393664, 7785238756, 24395316100, 7785238756, 213393664, 252004, 1, 1, 1026169
Offset: 1

Views

Author

Roger L. Bagula, Dec 13 2010

Keywords

Comments

Row sums are A168562.

Examples

			1;
1, 1;
1, 16, 1;
1, 121, 121, 1;
1, 676, 4356, 676, 1;
1, 3249, 91204, 91204, 3249, 1;
1, 14400, 1418481, 5837056, 1418481, 14400, 1;
		

Crossrefs

Programs

  • Mathematica
    << DiscreteMath`Combinatorica`;
    a = Table[Table[Eulerian[n + 1, m]^2, {m, 0, n}], {n, 0, 10}];
    Flatten[%]

A178048 Triangle T(n, m) = ( |-A008292(n+1,m+1)^2 + 2*binomial(n, m)^2| + A008292(n+1,m+1)*binomial(n, m) )/2 read by rows.

Original entry on oeis.org

1, 1, 1, 1, 8, 1, 1, 68, 68, 1, 1, 374, 2340, 374, 1, 1, 1742, 47012, 47012, 1742, 1, 1, 7524, 717948, 2942288, 717948, 7524, 1, 1, 31320, 9259560, 122248688, 122248688, 9259560, 31320, 1, 1, 127946, 106900560, 3895086794, 12203119800, 3895086794, 106900560, 127946, 1
Offset: 0

Views

Author

Roger L. Bagula, May 18 2010

Keywords

Examples

			The triangle starts in row n=0 with columns 0 <= m <= n as
  1;
  1,      1;
  1,      8,         1;
  1,     68,        68,          1;
  1,    374,      2340,        374,           1;
  1,   1742,     47012,      47012,        1742,          1;
  1,   7524,    717948,    2942288,      717948,       7524,         1;
  1,  31320,   9259560,  122248688,   122248688,    9259560,     31320,      1;
  1, 127946, 106900560, 3895086794, 12203119800, 3895086794, 106900560, 127946, 1;
		

Crossrefs

Programs

  • Maple
    A178048 := proc(n,m) binomial(n,m)*A008292(n+1,m+1)+abs( -A008292(n+1,m+1)^2+2*binomial(n,m)^2) ; %/2; end proc:
    seq(seq(A178048(n,k),k=0..n),n=0..10) ; # R. J. Mathar, Nov 26 2010
  • Mathematica
    << DiscreteMath`Combinatorica`
    t[n_, m_] = (Abs[2*Binomial[n, m]^2 - Eulerian[n + 1, m]^2] + Binomial[n, m]*Eulerian[n + 1, m])/2;
    Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];
    Flatten[%]

Formula

T(n, m) = T(n,n-m).

Extensions

Definition corrected by R. J. Mathar, Nov 26 2010

A178232 A triangle sequence derived from setting an Euler numbers A122045 generalization equal to the Eulerian numbers A008292 to get a generating function expansion: p(x,t) = ((-1 + exp(x)) (-1 + x)/(-1 + exp(t*x) + t - exp(t)* x)).

Original entry on oeis.org

0, 0, 1, 6, 1, 1, 36, 8, 3, 7, 1, 240, 60, -20, 81, 11, 21, 1, 1800, 480, -510, 822, 143, 173, 123, 51, 1, 15120, 4200, -7560, 8526, 2450, 239, 2381, 435, 715, 113, 1, 141120, 40320, -102480, 93744, 43512, -21320, 36991, 2943, 11035, 4035, 3139, 239, 1
Offset: 0

Views

Author

Roger L. Bagula, May 23 2010

Keywords

Comments

The first column gives the Lah numbers A001286: (n - 1)*n!/2;
{0,0,1, 6, 36, 240, 1800, 15120, 141120, 1451520, ...}.
Row sums are {0, 0, 1, 8, 55, 394, 3083, 26620, 253279, 2642390, 30052699, ...}.
The equation solved in the integer q was
q*exp(x*t)/(q - 1 + exp(t)) - (1 - t)/(1 - t*exp(x*(1 - t))) = 0.
Factors and the n! first term from taken out in Mathematica to give a more simple set of coefficients.
The idea in solving for an integer q here is to get a polynomial that behaves as a generalization of both types.
No q-form value for q=n=0,1 is expected.

Examples

			{0},
{0},
{1},
{6, 1, 1},
{36, 8, 3, 7, 1},
{240, 60, -20, 81, 11, 21, 1},
{1800, 480, -510, 822, 143, 173, 123, 51, 1},
{15120, 4200, -7560, 8526, 2450, 239, 2381, 435, 715, 113, 1},
{141120, 40320, -102480, 93744, 43512, -21320, 36991, 2943, 11035, 4035, 3139, 239, 1},
{1451520, 423360, -1391040, 1103760, 763056, -585432, 527544, 71353, 82513, 107377, 39589, 36349, 11947, 493, 1},
{16329600, 4838400, -19504800, 13940640, 13361040, -12088080, 7137270, 2643650, -749001, 2527719, 165459, 900099, 256743, 251073, 41883, 1003, 1}
		

References

  • Steve Roman, The Umbral Calculus, Dover Publications, New York (1984), pp. 78-79.
  • L. Comtet, Advanced Combinatorics, Reidel, Holland, 1978, page 245.

Crossrefs

Programs

  • Mathematica
    p[t_] = ((-1 + Exp[x]) (-1 + x)/(-1 + Exp[t*x] + t - Exp[t]* x));
    a = Table[ CoefficientList[FullSimplify[ExpandAll[(FullSimplify[ExpandAll[ -(1/((-1 + Exp[x])*(-1 + x)))*x^(n + 1)*n!*SeriesCoefficient[ Series[p[t], {t, 0, 30}], n]]] - n!)/(x^2*(-1 + x))]], x], {n, 0, 10}] Flatten[a]

Formula

p(x,t) = ((-1 + exp(x)) (-1 + x)/(-1 + exp(t*x) + t - exp(t)* x)).
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