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.

Showing 1-10 of 35 results. Next

A144380 Third subdiagonal of A142458: a(n) = A142458(n+3,n).

Original entry on oeis.org

1, 166, 5482, 109640, 1709675, 23077694, 284433852, 3300384000, 36740695125, 397251942790, 4206505251886, 43874389439176, 452588032465727, 4630933106076350, 47101176806668160, 476947462419456864, 4813761757416769257, 48466731584985480870, 487104579690137249650, 4889039701269534580360
Offset: 1

Views

Author

Roger L. Bagula and Gary W. Adamson, Oct 01 2008

Keywords

Crossrefs

Programs

  • Magma
    [(1/162)*( 8*10^(n+3) - 30*(3*n +8)*7^(n+2) + 6*(9*n^2 +39*n +40)*4^(n+2) - (27*n^3 +135*n^2 +198*n +80)): n in [1..30]]; // G. C. Greubel, Mar 15 2022
    
  • Mathematica
    T[n_, k_, m_]:= T[n, k, m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1,k-1,m] + (m*k - m+1)*T[n-1,k,m]];
    A144380[n_]:= T[n+3, n, 3];
    Table[A144380[n], {n,30}] (* modified by G. C. Greubel, Mar 15 2022 *)
  • Sage
    @CachedFunction
    def T(n,k,m):
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*T(n-1,k-1,m) + (m*k-m+1)*T(n-1,k,m)
    def A144380(n): return T(n+3, n, 3)
    [A144380(n) for n in (1..30)] # G. C. Greubel, Mar 15 2022

Formula

G.f.: x*(1 +126*x -483*x^2 -3884*x^3 +15300*x^4 -10848*x^5 -8960*x^6)/ ( (1-10*x) *(1-7*x)^2 *(1-4*x)^3 *(1-x)^4 ). - R. J. Mathar, Sep 14 2013
a(n) = (1/162)*( 8*10^(n+3) - 30*(3*n +8)*7^(n+2) + 6*(9*n^2 +39*n +40)*4^(n+2) - (27*n^3 +135*n^2 +198*n +80)). - G. C. Greubel, Mar 15 2022

A155491 Triangle T(n, k) = binomial(n+1, k)*A142458(n+1, k+1)/(k+1), read by rows.

Original entry on oeis.org

1, 1, 1, 1, 12, 1, 1, 78, 78, 1, 1, 415, 1820, 415, 1, 1, 2031, 27410, 27410, 2031, 1, 1, 9534, 330225, 959350, 330225, 9534, 1, 1, 43660, 3488884, 23935450, 23935450, 3488884, 43660, 1, 1, 196569, 33888576, 484631574, 1120179060, 484631574, 33888576, 196569, 1
Offset: 0

Views

Author

Roger L. Bagula, Jan 23 2009

Keywords

Examples

			Triangle begins as:
  1;
  1,      1;
  1,     12,        1;
  1,     78,       78,         1;
  1,    415,     1820,       415,          1;
  1,   2031,    27410,     27410,       2031,         1;
  1,   9534,   330225,    959350,     330225,      9534,        1;
  1,  43660,  3488884,  23935450,   23935450,   3488884,    43660,      1;
  1, 196569, 33888576, 484631574, 1120179060, 484631574, 33888576, 196569, 1;
		

Crossrefs

Cf. A001263 (m=0), A155467 (m=1), this sequence (m=3), A155493 (m=4).
Cf. A142458.

Programs

  • Mathematica
    t[n_, k_, m_]:= t[n,k,m]= If[k==1 || k==n, 1, (m*n-m*k+1)*t[n-1,k-1,m] + (m*k -(m -1))*t[n-1,k,m]];
    T[n_, k_, m_]:= Binomial[n+1,k]*t[n+1,k+1,m]/(k+1);
    Table[T[n,k,3], {n,0,12}, {k,0,n}]//Flatten (* modified by G. C. Greubel, Apr 01 2022 *)
  • Sage
    @CachedFunction
    def t(n,k,m):
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*t(n-1,k-1,m) + (m*k-m+1)*t(n-1,k,m)
    def T(n,k,m): return binomial(n+1,k)*t(n+1,k+1,m)/(k+1)
    flatten([[T(n,k,3) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Apr 01 2022

Formula

T(n, k) = binomial(n+1, k)*t(n, k, m)/(k+1), where t(n,k,m) = (m*(n-k)+1)*t(n-1,k-1,m) + (m*k-m+1)*t(n-1,k,m), t(n,1,m) = t(n,n,m) = 1, and m = 3.
From G. C. Greubel, Apr 01 2022: (Start)
T(n, k) = binomial(n+1, k)*A142458(n+1, k+1)/(k+1).
T(n, n-k) = T(n, k). (End)

Extensions

Edited by G. C. Greubel, Apr 01 2022

A172010 a(n) = 2*A142458(2*n, n)/(n+1).

Original entry on oeis.org

1, 26, 2741, 683870, 315704418, 234725594388, 257237392999893, 390832857108454838, 787178784737043042806, 2031210797603911366282796, 6536955866068372922068141666, 25676217636579568989377656129516, 120915166829869713032692550819662756, 672580820552232143302651758669053327784
Offset: 1

Views

Author

Roger L. Bagula, Nov 19 2010

Keywords

Crossrefs

Programs

  • Mathematica
    T[n_, k_, m_]:= T[n,k,m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1,k-1,m] + (m*k-m+ 1)*T[n-1,k,m]];
    a[n_]:= 2*T[2*n,n,3]/(n+1);
    Table[a[n], {n,30}] (* modified by G. C. Greubel, Mar 14 2022 *)
  • Sage
    @CachedFunction
    def T(n,k,m): # A142458
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*T(n-1,k-1,m) + (m*k-m+1)*T(n-1,k,m)
    [2*T(2*n,n,3)/(n+1) for n in (1..30)] # G. C. Greubel, Mar 14 2022

Formula

a(n) = 2*A142458(2*n, n)/(n+1).

Extensions

Name corrected and more terms added by G. C. Greubel, Mar 14 2022

A144381 a(n) = A142458(n+5, n). Fifth diagonal of A142458 triangle.

Original entry on oeis.org

1, 677, 47175, 1709675, 44451550, 947113254, 17716715490, 302925749370, 4856552119935, 74258231957275, 1095758678253041, 15736592058221517, 221321453958111620, 3062416225698505060, 41836761536767296660, 565817483249269872324, 7591501608353930033805, 101209790951020335444705
Offset: 1

Views

Author

Roger L. Bagula and Gary W. Adamson, Oct 01 2008

Keywords

Crossrefs

Programs

  • Magma
    [(1/1944)*((27*n^3 + 216*n^2 + 549*n + 440)*(3*n + 2 - 2*4^(n + 4)) +
       60*(9*n^2 + 57*n + 88)*7^(n + 3) - 32*(3*n + 11)*10^(n + 4) +
    880*13^(n + 3)): n in [1..30]]; // G. C. Greubel, Mar 16 2022
    
  • Mathematica
    T[n_, k_, m_]:= T[n, k, m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1, k-1, m] + (m*k-m+1)*T[n-1, k, m]];
    A144381[n_]:= T[n+4,n,3];
    Table[A144381[n], {n,30}] (* modified by G. C. Greubel, Mar 16 2022 *)
  • Sage
    @CachedFunction
    def T(n,k,m): # A144381
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*T(n-1,k-1,m) + (m*k-m+1)*T(n-1,k,m)
    def A144381(n): return T(n+4, n, 3)
    [A144381(n) for n in (1..30)] # G. C. Greubel, Mar 16 2022

Formula

a(n) = A142458(n+5, n).
From G. C. Greubel, Mar 16 2022: (Start)
G.f.: x*(1 +602*x -1080*x^2 -172614*x^3 +1780275*x^4 -5025348*x^5 -7549548*x^6 +60043488*x^7 -99645984*x^8 +39979520*x^9 +27596800*x^10)/((1-x)^5*(1-4*x)^4*(1-7*x)^3*(1-10*x)^2*(1-13*x)).
a(n) = (1/1944)*((27*n^3 +216*n^2 +549*n +440)*(3*n +2 - 2*4^(n+4)) +
60*(9*n^2 +57*n +88)*7^(n+3) -32*(3*n+11)*10^(n+4) + 880*13^(n+3)). (End)

Extensions

Edited by G. C. Greubel, Mar 16 2022

A225433 Triangle T(n, k) = T(n, k-1) + (-1)^k*A142458(n+2, k+1) if k <= floor(n/2), otherwise T(n, n-k), with T(n, 0) = T(n, n) = 1, read by rows.

Original entry on oeis.org

1, 1, 1, 1, -38, 1, 1, -165, -165, 1, 1, -676, 4806, -676, 1, 1, -2723, 44452, 44452, -2723, 1, 1, -10914, 362895, -1346780, 362895, -10914, 1, 1, -43681, 2780367, -20297327, -20297327, 2780367, -43681, 1, 1, -174752, 20554588, -263879264, 683233990, -263879264, 20554588, -174752, 1
Offset: 0

Views

Author

Roger L. Bagula, May 07 2013

Keywords

Examples

			The triangle begins:
  1;
  1,      1;
  1,    -38,       1;
  1,   -165,    -165,         1;
  1,   -676,    4806,      -676,         1;
  1,  -2723,   44452,     44452,     -2723,       1;
  1, -10914,  362895,  -1346780,    362895,  -10914,      1;
  1, -43681, 2780367, -20297327, -20297327, 2780367, -43681, 1;
		

Crossrefs

Programs

  • Maple
    See Maple program in A159041.
  • Mathematica
    (* First program *)
    T[n_, k_, m_]:= T[n, k, m]= If[k==0 || k==n, 1, (m*(n+1) -m*(k+1) +1)*T[n-1, k- 1, m] + (m*(k+1) -(m-1))*T[n-1, k, m] ];
    p[x_, n_]:= p[x, n]= Sum[x^i*If[i==Floor[n/2] && Mod[n, 2]==0, 0, If[i<= Floor[n/2], (-1)^i*T[n,i,3], -(-1)^(n-i)*T[n,i,3]]], {i,0,n}]/(1-x);
    Flatten[Table[CoefficientList[p[x, n], x], {n,0,12}]]
    (* Second program *)
    T[n_, k_, m_]:= T[n, k, m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1, k-1, m] + (m*k-m+1)*T[n-1, k, m]];
    A142458[n_, k_]:= T[n,k,3];
    A225433[n_, k_]:= A225433[n, k]= If[k==0 || k==n, 1, If[k<=Floor[n/2], A225433[n, k-1] +(-1)^k*A142458[n+2, k+1], A225433[n, n-k]]];
    Table[A225433[n, k], {n,0,12}, {k,0,n}]//Flatten (* G. C. Greubel, Mar 19 2022 *)
  • Sage
    @CachedFunction
    def T(n, k, m):
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*T(n-1, k-1, m) + (m*k-m+1)*T(n-1, k, m)
    def A142458(n,k): return T(n,k,3)
    @CachedFunction
    def A225433(n,k):
        if (k==0 or k==n): return 1
        elif (k <= (n//2)): return A225433(n,k-1) + (-1)^k*A142458(n+2,k+1)
        else: return A225433(n,n-k)
    flatten([[A225433(n,k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Mar 19 2022

Formula

From G. C. Greubel, Mar 19 2022: (Start)
T(n, k) = T(n, k-1) + (-1)^k*A142458(n+2, k+1) if k <= floor(n/2), otherwise T(n, n-k), with T(n, 0) = T(n, n) = 1.
T(n, n-k) = T(n, k). (End)

Extensions

Edited by N. J. A. Sloane, May 11 2013
Edited by G. C. Greubel, Mar 19 2022

A154425 a(n) = A142458(n, 1 + floor(n/2)).

Original entry on oeis.org

1, 1, 8, 39, 546, 5482, 109640, 1709675, 44451550, 947113254, 30307624128, 821539580358, 31218504053604, 1028949571999572, 45273781167981168, 1758747856988046771, 87937392849402338550, 3935893923685215214030
Offset: 1

Views

Author

Roger L. Bagula, Jan 09 2009

Keywords

Crossrefs

Cf. A142458.

Programs

  • Mathematica
    T[n_, k_, m_]:= T[n, k, m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1, k-1, m] + (m*k-m+1)*T[n-1, k, m]];
    A154425[n_]:= T[n, 1+Floor[n/2], 3];
    Table[A154425[n], {n, 30}] (* modified by G. C. Greubel, Mar 16 2022 *)
  • Sage
    @CachedFunction
    def T(n,k,m): # A142458
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*T(n-1,k-1,m) + (m*k-m+1)*T(n-1,k,m)
    def A154425(n): return T(n, 1 + (n//2), 3)
    [A154425(n) for n in (1..30)] # G. C. Greubel, Mar 16 2022

Formula

a(n) = A142458(n, 1 + floor(n/2)).

Extensions

Edited by G. C. Greubel, Mar 16 2022

A154596 a(n) = Sum_{j=1..n-1} A142458(n-1, k)*a(n - k), with a(1) = 1.

Original entry on oeis.org

1, 1, 2, 11, 129, 3214, 162491, 16306117, 3231430542, 1254563121783, 953359099059949, 1417753660258148022, 4128222097278496550683, 23571703478682225135264061, 264268834213603744830353397238
Offset: 1

Views

Author

Roger L. Bagula and Gary W. Adamson, Jan 12 2009

Keywords

Crossrefs

Programs

  • Mathematica
    T[n_, k_, m_]:= T[n, k, m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1, k-1, m] + (m*k-m+1)*T[n-1, k, m]];
    A142458[n_, k_]:= A142458[n, k] = T[n, k, 3];
    a[n_]:= a[n]= If[n==1, 1, Sum[A142458[n-1, j]*a[n-j], {j,n-1}]];
    Table[a[n], {n, 30}] (* modified by G. C. Greubel, Mar 16 2022 *)
  • Sage
    @CachedFunction
    def T(n,k,m):
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*T(n-1,k-1,m) + (m*k-m+1)*T(n-1,k,m)
    def A142458(n,k): return T(n,k,3)
    @CachedFunction
    def A154596(n): return 1 if (n==1) else sum( A142458(n-1, j)*A154596(n-j) for j in (1..n-1) )
    [A154596(n) for n in (1..30)] # G. C. Greubel, Mar 16 2022

Formula

a(n) = Sum_{j=1..n-1} A142458(n-1, k)*a(n-k), with a(1) = 1.

Extensions

Offset changed by G. C. Greubel, Mar 16 2022

A167786 Triangle of z Transform coefficients from General Pascal [1,8,1} A142458 polynomials multiplied by factor 3^Floor[(2*k - 1)/3].

Original entry on oeis.org

0, 3, 3, 6, 9, 45, 45, 27, 234, 540, 360, 27, 315, 1305, 1980, 990, 81, 1026, 6750, 18360, 20790, 8316, 243, 3807, 26379, 115830, 234630, 212058, 70686, 243, 7938, 37800, 177660, 582120, 939708, 706860, 201960, 729, 26001, 280827, 873180, 3087315
Offset: 0

Views

Author

Roger L. Bagula, Nov 12 2009

Keywords

Comments

Row sums are:
{0, 3, 9, 99, 1161, 4617, 55323, 663633, 2654289, 31850739, 382206681...}
These are a sequence of Infinite sums that give A142458.
Even terms are factored by (1+2*n) which is the MacMahon (1+2*n)^k,but the polynomials seem fundamental
other than that.
A060187 MacMahon gives A013609 Triangle of coefficients in expansion of (1 + 2x)^n.
I looked for a simple infinite sum for the {1,8,1} and failed.
This reasoning comes from finding that the general z Transform polynomials are
related to the Eulerian: in fact this type of Eulerian polynomials A008292 gives (1+n)^k binomial.
The polynomials given here form a set of infinite sum sequences.

Examples

			{0},
{3},
{3, 6},
{9, 45, 45},
{27, 234, 540, 360},
{27, 315, 1305, 1980, 990},
{81, 1026, 6750, 18360, 20790, 8316},
{243, 3807, 26379, 115830, 234630, 212058, 70686},
{243, 7938, 37800, 177660, 582120, 939708, 706860, 201960},
{729, 26001, 280827, 873180, 3087315, 8058204, 10814958, 6967620, 1741905},
{2187, -308610, 1076490, 7334820, 17120565, 48411594, 104968710, 120570120, 67934295, 15096510}
		

Crossrefs

Programs

  • Mathematica
    m = 3 A[n_, 1] := 1 A[n_, n_] := 1
    A[n_, k_] := (m*n - m*k + 1)A[n - 1, k - 1] + (m*k - (m - 1))A[n - 1, k]
    a = Table[A[n, k], {n, 10}, {k, n}]
    p[x_, n_] = x*Sum[a[[n, k]]*x^(k - 1), {k, 1, n}]/(x - 1)
    b = Table[p[x, n], {n, 0, 10}]
    Table[3^Floor[(2*k - 1)/3]*CoefficientList[ExpandAll[ InverseZTransform[b[[k]], x, n] /. UnitStep[ -1 + n] -> 1], n], {k, 1, Length[b]}]

Formula

m=3;
A(n,k)= (m*n - m*k + 1)A(n - 1, k - 1} + (m*k - (m - 1))A(n - 1, k)
q(n,k)=InverseZTransform[x*Sum[a[[n, k]]*x^(k - 1), {k, 1, n}]/(x - 1)^n, x, k]
out_n,k=3^Floor[(2*k - 1)/3]*coefficients(q[n,k])

A168295 Triangle T(n, k) = coefficients of (p(x,n)), where p(x, n) = (n-1)! * Sum_{j=1..n} A142458(n, j)*binomial(x+j-1, n-1), read by rows.

Original entry on oeis.org

1, 1, 2, 2, 10, 10, 6, 52, 120, 80, 24, 280, 1160, 1760, 880, 120, 1520, 10000, 27200, 30800, 12320, 720, 11280, 78160, 343200, 695200, 628320, 209440, 5040, 164640, 784000, 3684800, 12073600, 19490240, 14660800, 4188800, 40320, 1438080, 15532160, 48294400, 170755200, 445688320, 598160640, 385369600, 96342400
Offset: 1

Views

Author

Roger L. Bagula, Nov 22 2009

Keywords

Examples

			Triangle begins as:
     1;
     1,      2;
     2,     10,     10;
     6,     52,    120,      80;
    24,    280,   1160,    1760,      880;
   120,   1520,  10000,   27200,    30800,    12320;
   720,  11280,  78160,  343200,   695200,   628320,   209440;
  5040, 164640, 784000, 3684800, 12073600, 19490240, 14660800, 4188800;
		

Crossrefs

Programs

  • Mathematica
    T[n_, k_, m_]:= T[n, k, m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1, k-1, m] + (m*k-m+1)*T[n-1, k, m]];
    A142458[n_, k_]:= A142458[n, k]= T[n,k,3];
    p[x_, n_]:= p[x, n]= Sum[A142458[n,k]*Pochhammer[x+k-n+1, n-1], {k, n}];
    Table[CoefficientList[p[x, n], x], {n, 1, 12}]//Flatten (* modified by G. C. Greubel, Mar 17 2022 *)
  • Sage
    @CachedFunction
    def T(n,k,m): # A142458
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*T(n-1,k-1,m) + (m*k-m+1)*T(n-1,k,m)
    def A142458(n,k): return T(n,k,3)
    @CachedFunction
    def p(n,x): return sum( A142458(n,j)*rising_factorial(x+j-n+1, n-1) for j in (1..n))
    def A168295(n,k): return ( p(n,x) ).series(x,n+1).list()[k-1]
    flatten([[ A168295(n,k) for k in (1..n)] for n in (1..15)]) # G. C. Greubel, Mar 17 2022

Formula

T(n, k) = coefficients of (p(x,n)), where p(x, n) = (n-1)! * Sum_{j=1..n} A142458(n, j)*binomial(x+j-1, n-1).
From G. C. Greubel, Mar 17 2022: (Start)
T(n, k) = coefficients of (p(n, x)), where p(n, x) = Sum_{j=1..n} A142458(n, j)*Pochhammer(x+j-n+1, n-1).
T(n, 1) = (n-1)!.
T(n, n) = A008544(n-1). (End)

Extensions

Edited by G. C. Greubel, Mar 17 2022

A171274 Matrix inverse of A142458.

Original entry on oeis.org

1, -1, 1, 7, -8, 1, -235, 273, -39, 1, 35353, -41116, 5928, -166, 1, -22683409, 26382125, -3804940, 106900, -677, 1, 60147266239, -69954818244, 10089231945, -283474190, 1796973, -2724, 1, -648088191536203, 753764796604717, -108711714513099, 3054442698125, -19362601277, 29358651, -10915, 1
Offset: 1

Views

Author

Roger L. Bagula and Mats Granvik, Dec 06 2009

Keywords

Examples

			The triangle starts as:
            1;
           -1,            1;
            7,           -8,           1;
         -235,          273,         -39,          1;
        35353,       -41116,        5928,       -166,       1;
    -22683409,     26382125,    -3804940,     106900,    -677,     1;
  60147266239, -69954818244, 10089231945, -283474190, 1796973, -2724, 1;
		

Crossrefs

Cf. A142458.

Programs

  • Maple
    A142458:= proc(n,k) if n = k then 1; elif k > n or k < 1 then 0 ; else (3*n-3*k+1)*procname(n-1,k-1)+(3*k-2)*procname(n-1,k) ; end if; end proc:
    A171274 := proc(n,k) option remember; if k=n then 1; else -add( procname(n,j)*A142458(j,k),j=k+1..n);  end if; end proc:
    seq(seq(A171274(n,k), k=1..n), n=1..10); # R. J. Mathar, Jun 04 2011
  • Mathematica
    T[n_, k_, m_]:= T[n, k, m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1, k-1, m] + (m*k -m+1)*T[n-1, k, m]];
    A142458[n_, k_]:= T[n,k,3];
    A171274[n_, k_]:= A171274[n, k]= If[k==n, 1, -Sum[A171274[n, j]*A142458[j, k], {j,k+1,n}] ];
    Table[A171274[n, k], {n,12}, {k,n}]//Flatten (* modified by G. C. Greubel, Mar 18 2022 *)
  • Sage
    def T(n,k,m):
        if (k==1 or k==n): return 1
        else: return (m*(n-k)+1)*T(n-1,k-1,m) + (m*k-m+1)*T(n-1,k,m)
    def A142458(n,k): return T(n,k,3)
    @CachedFunction
    def A171274(n,k):
        if (k==n): return 1
        else: return (-1)*sum( A171274(n,j)*A142458(j,k) for j in (k+1..n) )
    flatten([[A171274(n,k) for k in (1..n)] for n in (1..12)]) # G. C. Greubel, Mar 18 2022

Formula

Sum_{j=k..n} T(n,j)*A142458(j,k) = delta(n,k), the Kronecker delta.
T(n, k) = (-1)*Sum_{j=k+1..n} T(n, j)*A142458(j, k), with T(n, n) = 1. - R. J. Mathar, Jun 04 2011
From G. C. Greubel, Mar 18 2022: (Start)
Sum_{k=1..n} T(n, k) = 0^(n-1).
T(n, n-1) = (-1)*A142458(n, 2). (End)
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