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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A135225 Pascal's triangle A007318 augmented with a leftmost border column of 1's.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 3, 1, 1, 1, 4, 6, 4, 1, 1, 1, 5, 10, 10, 5, 1, 1, 1, 6, 15, 20, 15, 6, 1, 1, 1, 7, 21, 35, 35, 21, 7, 1, 1, 1, 8, 28, 56, 70, 56, 28, 8, 1
Offset: 0

Views

Author

Gary W. Adamson, Nov 23 2007

Keywords

Comments

Row sums give A094373.
From Peter Bala, Sep 08 2011: (Start)
This augmented Pascal array, call it P, has interesting connections with the Bernoulli polynomials B(n,x). The infinitesimal generator S of P is the array such that exp(S) = P. The array S is obtained by augmenting the infinitesimal generator A132440 of the Pascal triangle with an initial column [0, 0, 1/2, 1/6, 0, -1/30, ...] on the left. The entries in this column, after the first two zeros, are the Bernoulli values B(n,1), n>=1.
The array P is also connected with the problem of summing powers of consecutive integers. In the array P^n, the entry in position p+1 of the first column is equal to sum {k = 1..n} k^p - see the Example section below.
For similar results for the square of Pascal's triangle see A062715.
Note: If we augment Pascal's triangle with the column [1, 1, x, x^2, x^3, ...] on the left, the resulting lower unit triangular array has the Bernoulli polynomials B(n,x) in the first column of its infinitesimal generator. The present case is when x = 1.
(End)

Examples

			First few rows of the triangle:
  1;
  1, 1;
  1, 1, 1;
  1, 1, 2, 1;
  1, 1, 3, 3, 1;
  1, 1, 4, 6, 4, 1;
...
The infinitesimal generator for P begins:
  /0
  |0.......0
  |1/2.....1...0
  |1/6.....0...2....0
  |0.......0...0....3....0
  |-1/30...0...0....0....4....0
  |0.......0...0....0....0....5....0
  |1/42....0...0....0....0....0....6....0
  |...
  \
The array P^n begins:
  /1
  |1+1+...+1........1
  |1+2+...+n........n.........1
  |1+2^2+...+n^2....n^2.....2*n........1
  |1+2^3+...+n^3....n^3.....3*n^2....3*n.......1
  |...
  \
More generally, the array P^t, defined as exp(t*S) for complex t, begins:
  /1
  |B(1,1+t)-B(1,1)..........1
  |1/2*(B(2,1+t)-B(2,1))....t.........1
  |1/3*(B(3,1+t)-B(3,1))....t^2.....2*t........1
  |1/4*(B(4,1+t)-B(4,1))....t^3.....3*t^2....3*t.......1
  |...
  \
		

Crossrefs

Programs

  • GAP
    T:= function(n,k)
        if k=0 then return 1;
        else return Binomial(n-1,k-1);
        fi; end;
    Flat(List([0..10], n-> List([0..n], k-> T(n,k) ))); # G. C. Greubel, Nov 19 2019
  • Magma
    T:= func< n, k | k eq 0 select 1 else Binomial(n-1, k-1) >;
    [T(n,k): k in [0..n], n in [0..10]]; // G. C. Greubel, Nov 19 2019
    
  • Maple
    T:= proc(n, k) option remember;
          if k=0 then 1
        else binomial(n-1, k-1)
          fi; end:
    seq(seq(T(n, k), k=0..n), n=0..10); # G. C. Greubel, Nov 19 2019
  • Mathematica
    T[n_, k_]:= T[n, k]= If[k==0, 1, Binomial[n-1, k-1]]; Table[T[n, k], {n, 0, 10}, {k, 0, n}]//Flatten (* G. C. Greubel, Nov 19 2019 *)
  • PARI
    T(n,k) = if(k==0, 1, binomial(n-1, k-1)); \\ G. C. Greubel, Nov 19 2019
    
  • Sage
    @CachedFunction
    def T(n,k):
        if (k==0): return 1
        else: return binomial(n-1, k-1)
    [[T(n,k) for k in (0..n)] for n in (0..10)] # G. C. Greubel, Nov 19 2019
    

Formula

A103451 * A007318 * A000012(signed), where A000012(signed) = (1; -1,1; 1,-1,1; ...); as infinite lower triangular matrices.
Given A007318, binomial(n,k) is shifted to T(n+1,k+1) and a leftmost border of 1's is added.

Extensions

Corrected by R. J. Mathar, Apr 16 2013

A154325 Triangle with interior all 2's and borders 1.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 2, 2, 1, 1, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1
Offset: 0

Views

Author

Paul Barry, Jan 07 2009

Keywords

Comments

This triangle follows a general construction method as follows: Let a(n) be an integer sequence with a(0)=1, a(1)=1. Then T(n,k,r):=[k<=n](1+r*a(k)*a(n-k)) defines a symmetrical triangle.
Row sums are n + 1 + r*Sum_{k=0..n} a(k)*a(n-k) and central coefficients are 1+r*a(n)^2.
Here a(n)=1-0^n and r=1. Row sums are A004277.
Eigensequence of the triangle = A000129, the Pell sequence. - Gary W. Adamson, Feb 12 2009
Inverse has general element T(n,k)*(-1)^(n-k). - Paul Barry, Oct 06 2010

Examples

			Triangle begins
  1;
  1, 1;
  1, 2, 1;
  1, 2, 2, 1;
  1, 2, 2, 2, 1;
  1, 2, 2, 2, 2, 1;
  1, 2, 2, 2, 2, 2, 1;
From _Paul Barry_, Oct 06 2010: (Start)
Production matrix is
  1,  1;
  0,  1, 1;
  0, -1, 0, 1;
  0,  1, 0, 0, 1;
  0, -1, 0, 0, 0, 1;
  0,  1, 0, 0, 0, 0, 1;
  0, -1, 0, 0, 0, 0, 0, 1;
  0,  1, 0, 0, 0, 0, 0, 0, 1; (End)
		

Crossrefs

Programs

  • Mathematica
    a[n_] :=
     If[Length@
        NestWhileList[# -
           Floor[(Sqrt[8 # + 1] - 1)/2] (Floor[(Sqrt[8 # + 1] - 1)/2] + 1)/
    2 &, n, # > 1 &] <= 2, 1, 2] (* David Naccache, Jul 13 2025 *)
  • PARI
    row(n) = vector(n+1, k, k--; (2-0^(k*(n-k)))); \\ Michel Marcus, Jul 13 2025

Formula

Number triangle T(n,k) = [k<=n](2-0^(n-k)-0^k+0^(n+k)) = [k<=n](2-0^(k*(n-k))).
a(n) = 2 - A103451(n). - Omar E. Pol, Jan 18 2009

Extensions

More terms from Michel Marcus, Jul 13 2025

A132735 Triangle T(n,k) = binomial(n,k) + 1 with T(n,0) = T(n,n) = 1, read by rows.

Original entry on oeis.org

1, 1, 1, 1, 3, 1, 1, 4, 4, 1, 1, 5, 7, 5, 1, 1, 6, 11, 11, 6, 1, 1, 7, 16, 21, 16, 7, 1, 1, 8, 22, 36, 36, 22, 8, 1, 1, 9, 29, 57, 71, 57, 29, 9, 1, 1, 10, 37, 85, 127, 127, 85, 37, 10, 1, 1, 11, 46, 121, 211, 253, 211, 121, 46, 11, 1, 1, 12, 56, 166, 331, 463, 463, 331, 166, 56, 12, 1
Offset: 0

Views

Author

Gary W. Adamson, Aug 26 2007

Keywords

Examples

			First few rows of the triangle are:
  1;
  1, 1;
  1, 3,  1;
  1, 4,  4,  1;
  1, 5,  7,  5,  1;
  1, 6, 11, 11,  6, 1;
  1, 7, 16, 21, 16, 7, 1;
  ...
		

Crossrefs

Sequences of the form binomial(n, k) + q: A132823 (q=-2), A132044 (q=-1), A007318 (q=0), this sequence (q=1), A173740 (q=2), A173741 (q=4), A173742 (q=6).

Programs

  • Magma
    T:= func< n,k | k eq 0 or k eq n select 1 else Binomial(n,k) + 1 >;
    [T(n,k): k in [0..n], n in [0..12]]; // _G. C. Greubel, Feb 14 2021
  • Mathematica
    T[n_, k_]:= If[k==0||k==n, 1, Binomial[n,k] +1];
    Table[T[n,k], {n,0,12}, {k,0,n}]//Flatten (* G. C. Greubel, Feb 14 2021 *)
  • Sage
    def T(n, k): return 1 if (k==0 or k==n) else binomial(n, k) + 1
    flatten([[T(n,k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Feb 14 2021
    

Formula

T(n, k) = A007318(n,k) + 1 - A103451(n,k), an infinite lower triangular matrix.
T(n,0) = T(n,n) = 1; T(n,k) = C(n,k) + 1 otherwise. - Franklin T. Adams-Watters, Jul 06 2009
Sum_{k=0..n} T(n, k) = 2^n + n - 1 + [n=0] = A132736(n). - G. C. Greubel, Feb 14 2021

Extensions

Corrected and extended by Franklin T. Adams-Watters, Jul 06 2009

A173740 Triangle T(n,k) = binomial(n,k) + 2 for 1 <= k <= n - 1, n >= 2, and T(n,0) = T(n,n) = 1 for n >= 0, read by rows.

Original entry on oeis.org

1, 1, 1, 1, 4, 1, 1, 5, 5, 1, 1, 6, 8, 6, 1, 1, 7, 12, 12, 7, 1, 1, 8, 17, 22, 17, 8, 1, 1, 9, 23, 37, 37, 23, 9, 1, 1, 10, 30, 58, 72, 58, 30, 10, 1, 1, 11, 38, 86, 128, 128, 86, 38, 11, 1, 1, 12, 47, 122, 212, 254, 212, 122, 47, 12, 1, 1, 13, 57, 167, 332, 464, 464, 332, 167, 57, 13, 1
Offset: 0

Views

Author

Roger L. Bagula, Feb 23 2010

Keywords

Comments

For n >= 1, row n sums to A131520(n).

Examples

			Triangle begins:
  1;
  1,  1;
  1,  4,  1;
  1,  5,  5,   1;
  1,  6,  8,   6,   1;
  1,  7, 12,  12,   7,   1;
  1,  8, 17,  22,  17,   8,   1;
  1,  9, 23,  37,  37,  23,   9,   1;
  1, 10, 30,  58,  72,  58,  30,  10,  1;
  1, 11, 38,  86, 128, 128,  86,  38, 11,  1;
  1, 12, 47, 122, 212, 254, 212, 122, 47, 12, 1;
  ...
		

Crossrefs

Sequences of the form binomial(n, k) + q: A132823 (q=-2), A132044 (q=-1), A007318 (q=0), A132735 (q=1), this sequence (q=2), A173741 (q=4), A173742 (q=6).

Programs

  • Magma
    T:= func< n,k | k eq 0 or k eq n select 1 else Binomial(n,k) + 2 >;
    [T(n,k): k in [0..n], n in [0..12]]; // G. C. Greubel, Feb 13 2021
  • Mathematica
    T[n_, m_] = Binomial[n, m] + 2*If[m*(n - m) > 0, 1, 0];
    Flatten[Table[T[n, m], {n, 0, 10}, {m, 0, n}]]
  • Maxima
    T(n,k) := if k = 0 or k = n then 1 else binomial(n, k) + 2$
    create_list(T(n, k), n, 0, 12, k, 0, n); /* Franck Maminirina Ramaharo, Dec 08 2018 */
    
  • Sage
    def T(n, k): return 1 if (k==0 or k==n) else binomial(n, k) + 2
    flatten([[T(n,k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Feb 13 2021
    

Formula

From Franck Maminirina Ramaharo, Dec 08 2018:(Start)
T(n,k) = A007318(n,k) + 2*(1 - A103451(n,k)).
T(n,k) = 3*A007318(n,k) - 2*A132044(n,k).
n-th row polynomial is 1 - (-1)^(2^n) + (1 + x)^n + 2*(x - x^n)/(1 - x).
G.f.: (1 - (1 + x)*y + 3*x*y^2 - 2*(x + x^2)*y^3)/((1 - y)*(1 - x*y)*(1 - y - x*y)).
E.g.f.: (2 - 2*x + 2*x*exp(y) - 2*exp(x*y) + (1 - x)*exp((1 + x)*y))/(1 - x). (End)
Sum_{k=0..n} T(n, k) = 2^n + 2*(n - 1 + [n=0]) = 2*A100314(n). - G. C. Greubel, Feb 13 2021

Extensions

Edited and name clarified by Franck Maminirina Ramaharo, Dec 08 2018

A132731 Triangle T(n,k) = 2 * binomial(n,k) - 2 with T(n,0) = T(n,n) = 1, read by rows.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 1, 4, 4, 1, 1, 6, 10, 6, 1, 1, 8, 18, 18, 8, 1, 1, 10, 28, 38, 28, 10, 1, 1, 12, 40, 68, 68, 40, 12, 1, 1, 14, 54, 110, 138, 110, 54, 14, 1, 1, 16, 70, 166, 250, 250, 166, 70, 16, 1, 1, 18, 88, 238, 418, 502, 418, 238, 88, 18, 1
Offset: 0

Views

Author

Gary W. Adamson, Aug 26 2007

Keywords

Examples

			First few rows of the triangle are:
  1;
  1,  1;
  1,  2,  1;
  1,  4,  4,  1;
  1,  6, 10,  6,  1;
  1,  8, 18, 18,  8,  1;
  1, 10, 28, 38, 28, 10,  1;
  1, 12, 40, 68, 68, 40, 12, 1;
  ...
		

Crossrefs

Cf. A000012, A007318, A103451, A132044, A132732 (row sums).

Programs

  • Magma
    T:= func< n,k | k eq 0 or k eq n select 1 else 2*Binomial(n,k) - 2 >;
    [T(n,k): k in [0..n], n in [0..12]]; // _G. C. Greubel, Feb 14 2021
  • Mathematica
    T[n_, k_]:= If[k==0 || k==n, 1, 2*Binomial[n, k] - 2];
    Table[T[n, k], {n,0,12}, {k,0,n}]//Flatten (* G. C. Greubel, Feb 14 2021 *)
  • PARI
    t(n,k) =  2*binomial(n, k) + ((k==0) || (k==n)) - 2*(k<=n); \\ Michel Marcus, Feb 12 2014
    
  • Sage
    def T(n, k): return 1 if (k==0 or k==n) else 2*binomial(n, k) - 2
    flatten([[T(n,k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Feb 14 2021
    

Formula

T(n, k) = 2*A007318 + A103451 - 2*A000012, an infinite lower triangular matrix.
From G. C. Greubel, Feb 14 2021: (Start)
T(n, k) = 2*binomial(n, k) - 2 with T(n, 0) = T(n, n) = 1.
T(n, k) = 2*A132044(n, k) with T(n, 0) = T(n, n) = 1.
Sum_{k=0..n} T(n, k) = 2^(n+1) - 2*n - [n=0] = A132732(n). (End)

Extensions

Corrected by Jeremy Gardiner, Feb 02 2014
More terms from Michel Marcus, Feb 12 2014

A132749 Triangle T(n,k) = binomial(n, k) with T(n, 0) = 2, read by rows.

Original entry on oeis.org

1, 2, 1, 2, 2, 1, 2, 3, 3, 1, 2, 4, 6, 4, 1, 2, 5, 10, 10, 5, 1, 2, 6, 15, 20, 15, 6, 1, 2, 7, 21, 35, 35, 21, 7, 1, 2, 8, 28, 56, 70, 56, 28, 8, 1, 2, 9, 36, 84, 126, 126, 84, 36, 9, 1, 2, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1, 2, 11, 55, 165, 330, 462, 462, 330, 165, 55, 11, 1
Offset: 0

Views

Author

Gary W. Adamson, Aug 28 2007

Keywords

Comments

Add 1 to all but the top entry in the left column of the Pascal matrix. - R. J. Mathar, Jan 18 2013

Examples

			First few rows of the triangle are:
  1;
  2, 1;
  2, 2,  1;
  2, 3,  3,  1;
  2, 4,  6,  4, 1;
  2, 5, 10, 10, 5, 1;
  ...
		

Crossrefs

Cf. A007318, A083318 (row sums), A103451.

Programs

  • Magma
    A132749:= func< n,k | k eq n select 1 else k eq 0 select 2 else Binomial(n,k) >;
    [A132749(n,k): k in [0..n], n in [0..12]]; // G. C. Greubel, Feb 16 2021
  • Mathematica
    T[n_, k_]:= If[k==n, 1, If[k==0, 2, Binomial[n, k]]];
    Table[T[n, k], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Feb 16 2021 *)
  • Sage
    def A132749(n,k): return 1 if k==n else 2 if k==0 else binomial(n,k)
    flatten([[A132749(n,k) for k in [0..n]] for n in [0..12]]) # G. C. Greubel, Feb 16 2021
    

Formula

T(n,k) = A103451(n,k) * A007318(n,k), an infinite lower triangular matrix.
From G. C. Greubel, Feb 16 2021: (Start)
T(n,k) = binomial(n, k) with T(n, 0) = 2 for n>0.
Sum_{k=0..n} T(n, k) = A083318(n) = 2^n + 1^n - 0^n. (End)

Extensions

More terms added by G. C. Greubel, Feb 16 2021

A173741 T(n,k) = binomial(n,k) + 4 for 1 <= k <= n - 1, n >= 2, and T(n,0) = T(n,n) = 1 for n >= 0, triangle read by rows.

Original entry on oeis.org

1, 1, 1, 1, 6, 1, 1, 7, 7, 1, 1, 8, 10, 8, 1, 1, 9, 14, 14, 9, 1, 1, 10, 19, 24, 19, 10, 1, 1, 11, 25, 39, 39, 25, 11, 1, 1, 12, 32, 60, 74, 60, 32, 12, 1, 1, 13, 40, 88, 130, 130, 88, 40, 13, 1, 1, 14, 49, 124, 214, 256, 214, 124, 49, 14, 1, 1, 15, 59, 169, 334, 466, 466, 334, 169, 59, 15, 1
Offset: 0

Views

Author

Roger L. Bagula, Feb 23 2010

Keywords

Comments

For n >= 1, row n sums to 2*A100314(n).

Examples

			Triangle begins:
  1;
  1,  1;
  1,  6,  1;
  1,  7,  7,   1;
  1,  8, 10,   8,   1;
  1,  9, 14,  14,   9,   1;
  1, 10, 19,  24,  19,  10,   1;
  1, 11, 25,  39,  39,  25,  11,   1;
  1, 12, 32,  60,  74,  60,  32,  12,  1;
  1, 13, 40,  88, 130, 130,  88,  40, 13,  1;
  1, 14, 49, 124, 214, 256, 214, 124, 49, 14, 1;
  ...
		

Crossrefs

Sequences of the form binomial(n, k) + q: A132823 (q=-2), A132044 (q=-1), A007318 (q=0), A132735 (q=1), A173740 (q=2), this sequence (q=4), A173742 (q=6).

Programs

  • Magma
    T:= func< n,k | k eq 0 or k eq n select 1 else Binomial(n,k) + 4 >;
    [T(n,k): k in [0..n], n in [0..12]]; // G. C. Greubel, Feb 13 2021
  • Mathematica
    T[n_, m_] = Binomial[n, m] + 4*If[m*(n - m) > 0, 1, 0];
    Flatten[Table[T[n, m], {n, 0, 10}, {m, 0, n}]]
  • Maxima
    T(n,k) := if k = 0 or k = n then 1 else binomial(n, k) + 4$
    create_list(T(n, k), n, 0, 12, k, 0, n); /* Franck Maminirina Ramaharo, Dec 09 2018 */
    
  • Sage
    def T(n, k): return 1 if (k==0 or k==n) else binomial(n, k) + 4
    flatten([[T(n,k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Feb 13 2021
    

Formula

From Franck Maminirina Ramaharo, Dec 09 2018:(Start)
T(n,k) = A007318(n,k) + 2*(1 - A103451(n,k)).
T(n,k) = 5*A007318(n,k) - 4*A132044(n,k).
n-th row polynomial is 2*(1 - (-1)^(2^n)) + (1 + x)^n + 4*(x - x^n)/(1 - x).
G.f.: (1 - (1 + x)*y + 5*x*y^2 - 4*(x + x^2)*y^3)/((1 - y)*(1 - x*y)*(1 - y - x*y)).
E.g.f.: (4 - 4*x + 4*x*exp(y) - 4*exp(x*y) + (1 - x)*exp((1 + x)*y))/(1 - x). (End)
Sum_{k=0..n} T(n, k) = 2^n + 4*(n - 1 + [n=0]) = 2*A100314(n). - G. C. Greubel, Feb 13 2021

Extensions

Edited and name clarified by Franck Maminirina Ramaharo, Dec 09 2018

A173742 Triangle T(n,k) = binomial(n,k) + 6 with T(n,0) = T(n,n) = 1 for n >= 0, read by rows.

Original entry on oeis.org

1, 1, 1, 1, 8, 1, 1, 9, 9, 1, 1, 10, 12, 10, 1, 1, 11, 16, 16, 11, 1, 1, 12, 21, 26, 21, 12, 1, 1, 13, 27, 41, 41, 27, 13, 1, 1, 14, 34, 62, 76, 62, 34, 14, 1, 1, 15, 42, 90, 132, 132, 90, 42, 15, 1, 1, 16, 51, 126, 216, 258, 216, 126, 51, 16, 1, 1, 17, 61, 171, 336, 468, 468, 336, 171, 61, 17, 1
Offset: 0

Views

Author

Roger L. Bagula, Feb 23 2010

Keywords

Comments

For n >= 1, row n sums to A131520(n) + A008586(n).

Examples

			Triangle begins:
  1;
  1,  1;
  1,  8,  1;
  1,  9,  9,   1;
  1, 10, 12,  10,   1;
  1, 11, 16,  16,  11,   1;
  1, 12, 21,  26,  21,  12,   1;
  1, 13, 27,  41,  41,  27,  13,   1;
  1, 14, 34,  62,  76,  62,  34,  14,  1;
  1, 15, 42,  90, 132, 132,  90,  42, 15,  1;
  1, 16, 51, 126, 216, 258, 216, 126, 51, 16, 1;
  ...
		

Crossrefs

Programs

  • Magma
    T:= func< n,k | k eq 0 or k eq n select 1 else Binomial(n,k) +6 >;
    [T(n,k): k in [0..n], n in [0..12]]; // G. C. Greubel, Feb 13 2021
  • Mathematica
    T[n_, m_] = Binomial[n, m] + 6*If[m*(n - m) > 0, 1, 0];
    Flatten[Table[T[n, m], {n, 0, 10}, {m, 0, n}]]
  • Maxima
    T(n,k) := if k = 0 or k = n then 1 else binomial(n, k) + 6$
    create_list(T(n, k), n, 0, 12, k, 0, n); /* Franck Maminirina Ramaharo, Dec 09 2018 */
    
  • Sage
    def T(n, k): return 1 if (k==0 or k==n) else binomial(n, k) + 6
    flatten([[T(n,k) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Feb 13 2021
    

Formula

From Franck Maminirina Ramaharo, Dec 09 2018: (Start)
T(n,k) = A007318(n,k) + 6*(1 - A103451(n,k)).
T(n,k) = 7*A007318(n,k) - 6*A132044(n,k).
n-th row polynomial is 3*(1 - (-1)^(2^n)) + (1 + x)^n + 6*(x - x^n)/(1 - x).
G.f.: (1 - (1 + x)*y + 7*x*y^2 - 6*(x + x^2)*y^3)/((1 - y)*(1 - x*y)*(1 - y - x*y)).
E.g.f.: (6 - 6*x + 6*x*exp(y) - 6*exp(x*y) + (1 - x)*exp((1 + x)*y))/(1 - x). (End)
Sum_{k=0..n} T(n, k) = 2^n + 6*n - 6 + 6*[n=0]. - G. C. Greubel, Feb 13 2021

Extensions

Edited and name clarified by Franck Maminirina Ramaharo, Dec 09 2018

A185784 Accumulation array of A107985, by antidiagonals.

Original entry on oeis.org

1, 4, 4, 10, 15, 10, 20, 36, 36, 20, 35, 70, 84, 70, 35, 56, 120, 160, 160, 120, 56, 84, 189, 270, 300, 270, 189, 84, 120, 280, 420, 500, 500, 420, 280, 120, 165, 396, 616, 770, 825, 770, 616, 396, 165, 220, 540, 864, 1120, 1260, 1260, 1120, 864, 540, 220, 286, 715, 1170, 1560, 1820, 1911, 1820, 1560, 1170, 715, 286, 364, 924, 1540, 2100, 2520, 2744, 2744, 2520, 2100, 1540, 924, 364, 455, 1170, 1980, 2750, 3375, 3780, 3920, 3780, 3375, 2750, 1980, 1170, 455, 560
Offset: 1

Views

Author

Clark Kimberling, Feb 03 2011

Keywords

Comments

Let W be the array given by w(1,1)=1, w(2,2)=-1, and w(n,k)=0 for all other (n,k).
Write "A < B" to indicate that an array B is the accumulation array of A (defined at A144112). Then W < A103451 < A002024 < A107985 < A185784 < A185785 < A185786.

Examples

			Northwest corner:
1....4....10....20....35
4....15...36....70....120
10...36...84....160...270
20...70...160...300...500
		

Crossrefs

Programs

  • Mathematica
    (* The code generates arrays A107985, A185784, A002024. *)
    f[n_,0]:=0;f[0,k_]:=0; (* used to form A002024 *)
    f[n_,k_]:=k*n(k+n)/2;
    TableForm[Table[f[n,k],{n,1,10},{k,1,15}]] (* A107985 *)
    s[n_,k_]:=Sum[f[i,j],{i,1,n},{j,1,k}]; (* accumulation array of {f(n,k)} *)
    FullSimplify[s[n,k]]
    TableForm[Table[s[n,k],{n,1,10},{k,1,15}]]  (* A185784 *)
    Table[s[n-k+1,k],{n,14},{k,n,1,-1}]//Flatten
    w[m_,n_]:=f[m,n]+f[m-1,n-1]-f[m,n-1]-f[m-1,n]/;Or[m>0,n>0];
    TableForm[Table[w[n,k],{n,1,10},{k,1,15}]] (* A002024 *)

Formula

T(n,k) = (n+k+1)*C(n+1,2)*C(k+1,2)/3, k>=0, n>=0.

A091918 Inverse of number triangle A091917.

Original entry on oeis.org

1, 2, 1, 4, 2, 1, 8, 3, 3, 1, 16, 4, 6, 4, 1, 32, 5, 10, 10, 5, 1, 64, 6, 15, 20, 15, 6, 1, 128, 7, 21, 35, 35, 21, 7, 1, 256, 8, 28, 56, 70, 56, 28, 8, 1, 512, 9, 36, 84, 126, 126, 84, 36, 9, 1, 1024, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1, 2048, 11, 55, 165, 330, 462, 462, 330
Offset: 0

Views

Author

Paul Barry, Feb 13 2004

Keywords

Comments

Essentially, Pascal's triangle A007318 with first column of 1's replaced by 2^n Row sums are A000225(n+1). Diagonal sums are A000225(n) + A000045(n).

Crossrefs

Cf. A103451.

Formula

Binomial transform of triangle A103451: (1; 1,1; 1,0,1; 1,0,0,1; ...). - Gary W. Adamson, Aug 08 2007
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