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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A144337 Triangle read by rows, A000012 * (2*A144328 - A000012).

Original entry on oeis.org

1, 2, 1, 3, 2, 3, 4, 3, 6, 5, 5, 4, 9, 10, 7, 6, 5, 12, 15, 14, 9, 7, 6, 15, 20, 21, 18, 11, 8, 7, 18, 25, 28, 27, 22, 13, 9, 8, 21, 30, 35, 36, 33, 26, 15, 10, 9, 24, 35, 42, 45, 44, 39, 30, 17, 11, 10, 27, 40, 49, 54, 55, 52, 45, 34, 19
Offset: 1

Views

Author

Gary W. Adamson and Roger L. Bagula, Sep 18 2008

Keywords

Comments

When the first column is removed from this triangle (A144337), the result is triangle A101447. - Georg Fischer, Aug 10 2023

Examples

			First few rows of the triangle:
   1;
   2,  1;
   3,  2,  3;
   4,  3,  6,  5;
   5,  4,  9, 10,  7;
   6,  5, 12, 15, 14,  9;
   7,  6, 15, 20, 21, 18, 11;
   8,  7, 18, 25, 28, 27, 22, 13;
   9,  8, 21, 30, 35, 36, 33, 26, 15;
  10,  9, 24, 35, 42, 45, 44, 39, 30, 17;
  ...
		

Crossrefs

Extensions

a(25) corrected by Georg Fischer, Aug 10 2023

A144693 Triangle read by rows, A000012 * (3*A144328 - 2*A000012), where A000012 means a lower triangular matrix of all 1's.

Original entry on oeis.org

1, 2, 1, 3, 2, 4, 4, 3, 8, 7, 5, 4, 12, 14, 10, 6, 5, 16, 21, 20, 13, 7, 6, 20, 28, 30, 26, 16, 8, 7, 24, 35, 40, 39, 32, 19, 9, 8, 28, 42, 50, 52, 48, 38, 22, 10, 9, 32, 49, 60, 65, 64, 57, 44, 25, 11, 10, 36, 56, 70, 78, 80, 76, 66, 50, 28
Offset: 1

Views

Author

Gary W. Adamson, Sep 19 2008

Keywords

Examples

			Partial sums by columns of the triangle (3*A144328 - 2*A000012):
  1;
  1, 1;
  1, 1, 4;
  1, 1, 4, 7;
  1, 1, 4, 7, 10;
  ...
First few rows of the triangle:
  1;
  2, 1
  3, 2,  4;
  4, 3,  8,  7;
  5, 4, 12, 14, 10;
  6, 5, 16, 21, 20, 13;
  7, 6, 20, 28, 30, 26, 16;
  8, 7, 24, 35, 40, 39, 32, 19;
  ...
		

Crossrefs

Programs

  • Magma
    A144693:= func< n,k | k eq 1 select n else (3*k-5)*(n-k+1) >;
    [A144693(n,k): k in [1..n], n in [1..12]]; // G. C. Greubel, Oct 19 2021
    
  • Mathematica
    T[n_, k_]:= (3*k -5 +3*Boole[k==1])*(n-k+1);
    Table[T[n, k], {n,12}, {k,n}]//Flatten (* G. C. Greubel, Oct 19 2021 *)
  • Sage
    def A144693(n,k): return (3*k -5 +3*bool(k==1))*(n-k+1)
    flatten([[A144693(n,k) for k in (1..n)] for n in (1..12)]) # G. C. Greubel, Oct 19 2021

Formula

Sum_{k=1..n} T(n, k) = A064808(n).
T(n, k) = (3*k -5 +3*[k=1])*(n-k+1). - G. C. Greubel, Oct 19 2021

A145972 Triangle read by rows, A000012 * A053121.

Original entry on oeis.org

1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 4, 3, 4, 1, 1, 4, 8, 4, 5, 1, 1, 9, 8, 13, 5, 6, 1, 1, 9, 22, 13, 19, 6, 7, 1, 1, 23, 22, 41, 19, 26, 7, 8, 1, 1, 23, 64, 41, 67, 26, 34, 8, 9, 1, 1, 65, 64, 131, 67, 101, 34, 43, 9, 10, 1, 1
Offset: 0

Views

Author

Keywords

Comments

Row sums = A036256: (1, 2, 4, 7, 13, 23, 43,...).

Examples

			A053121 starts:
1;
0, 1;
1, 0, 1;
0, 2, 0, 1;
...
Taking partial sums from the top, we get A145972:
1;
1, 1;
2, 1, 1;
2, 3, 1, 1;
4, 3, 4, 1, 1;
4, 8, 4, 5, 1, 1;
9, 8, 13, 5, 6, 1, 1;
9, 22, 13, 19, 6, 7, 1, 1;
23, 22, 41, 19, 26, 7, 8, 1, 1;
23, 64, 41, 67, 26, 34, 8, 9, 1, 1;
...
		

Crossrefs

Formula

Triangle read by rows, A000012 * A053121, = partial sums of column terms of triangle A053121.

A152194 Triangle read by rows, A034839 * A000012.

Original entry on oeis.org

1, 1, 2, 1, 4, 3, 8, 7, 1, 16, 15, 5, 32, 31, 16, 1, 64, 63, 42, 7, 128, 127, 99, 29, 1256, 255, 219, 93, 9, 512, 511, 466, 256, 46, 1, 1024, 1023, 968, 638, 176, 11, 2048, 2047, 1981, 1486, 562, 67, 1
Offset: 0

Views

Author

Gary W. Adamson, Nov 28 2008

Keywords

Comments

Row sums = A045891: (1, 1, 3, 7, 16, 36, 80, 176,...)

Examples

			First few rows of the triangle =
1;
1;
2, 1;
4, 3;
8, 7, 1;
16, 15, 5;
32, 31, 16, 1;
64, 63, 42, 7;
128, 127, 99, 29, 1;
256, 255, 219, 93, 9;
512, 511, 466, 256, 46, 1;
1024, 1023, 968, 638, 176, 11;
2048, 2047, 1981, 1486, 562, 67, 1;
...
		

Crossrefs

Formula

A034839 * A000012 = partial sums of A034839 by rows, starting from the right.

A153345 Triangle read by rows, A000012 * A055830.

Original entry on oeis.org

1, 2, 0, 4, 1, 0, 7, 4, 1, 0, 12, 11, 5, 1, 0, 20, 26, 17, 6, 1, 0, 33, 56, 48, 24, 7, 1, 0, 54, 114, 121, 78, 32, 8, 1, 0, 88, 223, 283, 223, 117, 41, 9, 1, 0, 143, 424, 627, 584, 372, 166, 51, 10, 1, 0, 232, 789, 1334, 1434, 1073, 579, 226, 62, 11, 1, 0, 376, 1444, 2750, 3352, 2879, 1818, 856, 298, 74, 12, 1, 0
Offset: 1

Views

Author

Gary W. Adamson, Dec 24 2008

Keywords

Comments

Row sums = Pell numbers, A000129: (1, 2, 5, 12, 29,...).
Left border = A000071.

Examples

			First few rows of the triangle =
1;
2, 0;
4, 1, 0;
7, 4, 1, 0;
12, 11, 5, 1, 0;
20, 26, 17, 6, 1, 0;
33, 56, 48, 24, 7, 1, 0;
54, 114, 121, 78, 32, 8, 1, 0;
88, 223, 283, 223, 117, 41, 9, 1, 0;
143, 424, 627, 584, 372, 166, 51, 10, 1, 0;
232, 789, 1334, 1434, 1073, 579, 226, 62, 11, 1, 0;
...
		

Crossrefs

Formula

Triangle read by rows, A000012 * triangle A055830 = partial sums of A055830 columns.

Extensions

a(21) = 0 inserted and more terms from Georg Fischer, May 29 2023

A153346 Triangle read by rows: A000012 * A153345.

Original entry on oeis.org

1, 3, 0, 7, 1, 0, 14, 5, 1, 0, 26, 16, 6, 1, 0, 46, 42, 23, 7, 1, 0, 79, 98, 71, 31, 8, 1, 0, 133, 212, 192, 109, 40, 9, 1, 0, 221, 435, 475, 332, 157, 50, 10, 1, 0, 364, 859, 1102, 916, 529, 216, 61, 11, 1, 0, 596, 1648, 2436, 2350, 1602, 795, 287, 73, 12, 1, 0, 972, 3092, 5186, 5702, 4481, 2613, 1143, 371, 86, 13, 1, 0
Offset: 0

Views

Author

Gary W. Adamson, Dec 24 2008

Keywords

Comments

Row sums = A048739: (1, 3, 8, 20, 49, 119, 288, ...).
Left border = A001924.

Examples

			First few rows of the triangle:
    1;
    3,    0;
    7,    1,    0;
   14,    5,    1,    0;
   26,   16,    6,    1,    0;
   46,   42,   23,    7,    1,   0
   79,   98,   71,   31,    8,   1,   0;
  133,  212,  192,  109,   40,   9,   1,  0;
  221,  435,  475,  332,  157,  50,  10,  1,  0;
  364,  859, 1102,  916,  529, 216,  61, 11,  1, 0;
  596, 1648, 2436, 2350, 1602, 795, 287, 73, 12, 1, 0;
  ...
		

Crossrefs

Extensions

a(44) = 0 corrected and more terms from Georg Fischer, Jun 05 2023

A157901 Triangle read by rows: A000012 * A157898.

Original entry on oeis.org

1, 1, 1, 2, 2, 2, 2, 4, 4, 4, 3, 6, 10, 8, 8, 3, 9, 16, 24, 16, 16, 4, 12, 28, 40, 56, 32, 32, 4, 16, 40, 80, 96, 128, 64, 64, 5, 20, 60, 120, 216, 224, 288, 128, 128, 5, 25, 80, 200, 336, 560, 512, 640, 256, 256, 6, 30, 110, 280, 616, 896, 1408, 1152, 1408, 512, 512
Offset: 0

Views

Author

Keywords

Comments

Multiplication of the lower triangular matrix A157898 from the left by A000012 means: these are partial column sums of A157898.

Examples

			First few rows of the triangle, n>=0:
  1;
  1,  1;
  2,  2,  2;
  2,  4,  4,   4;
  3,  6, 10,   8,   8;
  3,  9, 16,  24,  16,  16;
  4, 12, 28,  40,  56,  32,  32;
  4, 16, 40,  80,  96, 128,  64,  64;
  5, 20, 60, 120, 216, 224, 288, 128, 128;
  5, 25, 80, 200, 336, 560, 512, 640, 256, 256;
		

Crossrefs

Columns: A004526 (k=0), A002620 (k=1), A006584 (k=2), 4*A096338 (k=3), 8*A177747 (k=4), 16*A299337 (k=5), 32*A178440 (k=6).
Sums include: A105635(n+1) (row), A166486(n+1) (alternating sign diagonal), A232801(n+1) (diagonal).

Programs

  • Magma
    A011782:= func< n | n eq 0 select 1 else 2^(n-1) >;
    function t(n, k) // t = A059576
      if k eq 0 or k eq n then return A011782(n);
      else return 2*t(n-1, k-1) + 2*t(n-1, k) - (2 - 0^(n-2))*t(n-2, k-1);
      end if; return t;
    end function;
    A157898:= func< n, k | (&+[(-1)^(n-j)*Binomial(n, j)*t(j, k): j in [k..n]]) >;
    A157071:= func< n,k | (&+[A157898(j+k,k): j in [0..n-k]]) >;
    [A157071(n, k): k in [0..n], n in [0..12]]; // G. C. Greubel, Aug 27 2025
    
  • Mathematica
    t[n_, k_]:= t[n,k]= If[k==0 || k==n, 2^(n-1) +Boole[n==0]/2, 2*t[n-1,k-1] +2*t[n-1,k] - (2 -Boole[n==2])*t[n-2,k-1]]; (* t = A059576 *)
    A157898[n_, k_]:= A157898[n,k]= Sum[(-1)^(n-j)*Binomial[n,j]*t[j,k], {j,k,n}];
    A157901[n_, k_]:= A157901[n,k]= Sum[A157898[j+k,k], {j,0,n-k}];
    Table[A157901[n,k], {n,0,12}, {k,0,n}]//Flatten (* G. C. Greubel, Aug 27 2025 *)
  • SageMath
    @CachedFunction
    def t(n, k): # t = A059576
        if (k==0 or k==n): return bool(n==0)/2 + 2^(n-1) # A011782
        else: return 2*t(n-1, k-1) + 2*t(n-1, k) - (2 - 0^(n-2))*t(n-2, k-1)
    def A157898(n, k): return sum((-1)^(n+k-j)*binomial(n, j+k)*t(j+k, k) for j in range(n-k+1))
    def A157071(n,k): return sum(A157898(j+k,k) for j in range(n-k+1))
    print(flatten([[A157071(n,k) for k in range(n+1)] for n in range(10)])) # G. C. Greubel, Aug 27 2025

Formula

T(n,k) = Sum_{j=0..n} A157898(j,k).

Extensions

Edited by the Associate Editors of the OEIS, Apr 10 2009
More terms from G. C. Greubel, Aug 27 2025

A158822 Triangle read by rows, matrix triple product A000012 * A145677 * A000012.

Original entry on oeis.org

1, 3, 1, 6, 3, 2, 10, 6, 5, 3, 15, 10, 9, 7, 4, 21, 15, 14, 12, 9, 5, 28, 21, 20, 18, 15, 11, 6, 36, 28, 27, 25, 22, 18, 13, 7, 45, 36, 35, 33, 30, 26, 21, 15, 8, 55, 45, 44, 42, 39, 35, 30, 24, 17, 9, 66, 55, 54, 52, 49, 45, 40, 34, 27, 19, 10
Offset: 0

Views

Author

Gary W. Adamson and Roger L. Bagula, Mar 28 2009

Keywords

Examples

			First few rows of the triangle =
   1;
   3,  1;
   6,  3,  2;
  10,  6,  5,  3;
  15, 10,  9,  7,  4;
  21, 15, 14, 12,  9,  5;
  28, 21, 10, 18, 15, 11,  6;
  36, 28, 27, 25, 22, 18, 13,  7;
  45, 36, 35, 33, 30, 26, 21, 15,  8;
  55, 45, 44, 42, 39, 35, 30, 24, 17,  9;
  66, 55, 54, 52, 49, 45, 40, 34, 27, 19, 10;
  78, 66, 65, 63, 60, 56, 51, 45, 38, 30, 21, 11;
  91, 78, 77, 75, 72, 68, 63, 57, 50, 42, 33, 23, 12;
  ...
		

Crossrefs

Programs

  • Mathematica
    T[n_, k_]:= If[k==0, Binomial[n+2, 2], (n+1-k)*(n+k)/2];
    Table[T[n, k], {n,0,15}, {k,0,n}]//Flatten (* G. C. Greubel, Dec 26 2021 *)
  • Sage
    def A158822(n,k):
        if (k==0): return binomial(n+2, 2)
        else: return (n-k+1)*(n+k)/2
    flatten([[A158822(n,k) for k in (0..n)] for n in (0..15)]) # G. C. Greubel, Dec 26 2021

Formula

Triangle read by rows, A000012 * A145677 * A000012; where A000012 = an infinite lower triangular matrix: (1; 1,1; 1,1,1; ...), with all 1's.
From G. C. Greubel, Dec 26 2021: (Start)
T(n, k) = (n+1-k)*(n+k)/2 with T(n, 0) = binomial(n+2, 2).
Sum_{k=0..n} T(n, k) = (1/3)*(n+1)*(n^2 + 2*n + 3) = A006527(n+1).
Sum_{k=0..floor(n/2)} T(n-k, k) = binomial(n+2, 2) + A034828(n+1).
T(n, 1) = A000217(n).
T(n, 2) = A000096(n-1).
T(n, 3) = A055998(n-2).
T(2*n, n) = A134479(n). (End)

Extensions

Definition corrected by Michael Somos, Nov 05 2011

A158946 Triangle read by rows, A000012(signed) * A145677 * A000012.

Original entry on oeis.org

1, 1, 1, 2, 1, 2, 2, 2, 1, 3, 3, 2, 3, 1, 4, 3, 3, 2, 4, 1, 5, 4, 3, 4, 2, 5, 1, 6, 4, 4, 3, 5, 2, 6, 1, 7, 5, 4, 5, 3, 6, 2, 7, 1, 8, 5, 5, 4, 6, 3, 7, 2, 8, 1, 9, 6, 5, 6, 4, 7, 3, 8, 2, 9, 1, 10, 6, 6, 5, 7, 4, 8, 3, 9, 2, 10, 1, 11
Offset: 1

Views

Author

Gary W. Adamson, Mar 31 2009

Keywords

Comments

Row sums = A000982 starting with offset 1: (1, 2, 5, 8, 13, 18, 25,...).

Examples

			First few rows of the triangle =
1;
1, 1;
2, 1, 2;
2, 2, 1, 3;
3, 2, 3, 1, 4;
3, 3, 2, 4, 1, 5;
4, 3, 4, 2, 5, 1, 6;
4, 4, 3, 5, 2, 6, 1, 7;
5, 4, 5, 3, 6, 2, 7, 1, 8;
5, 5, 4, 6, 3, 7, 2, 8, 1, 9;
6, 5, 6, 4, 7, 3, 8, 2, 9, 1, 10;
6, 6, 5, 7, 4, 8, 3, 9, 2, 10, 1, 11;
7, 6, 7, 5, 8, 4, 9, 3, 10, 2, 11, 1, 12;
7, 7, 6, 8, 5, 9, 4, 10, 3, 11, 2, 12, 1, 13;
...
		

Crossrefs

Formula

Triangle read by rows, A000012(signed) * A145677 * A000012. A000012(signed) = an infinite lower triangular matrix with (1,-1,1,-1,...) in every column. A145677 = an infinite lower triangular matrix with all 1's as the left border, right border = (1, 1, 2, 3, 4, 5,...), and the rest zeros.

A166556 Triangle read by rows, A000012 * A047999.

Original entry on oeis.org

1, 2, 1, 3, 1, 1, 4, 2, 2, 1, 5, 2, 2, 1, 1, 6, 3, 2, 1, 2, 1, 7, 3, 3, 1, 3, 1, 1, 8, 4, 4, 2, 4, 2, 2, 1, 9, 4, 4, 2, 4, 2, 2, 1, 1, 10, 5, 4, 2, 4, 2, 2, 1, 2, 1, 11, 5, 5, 2, 4, 2, 2, 1, 3, 1, 1, 12, 6, 6, 3, 4, 2, 2, 1, 4, 2, 2, 1
Offset: 0

Views

Author

Gary W. Adamson, Oct 17 2009

Keywords

Examples

			First few rows of the triangle =
   1;
   2, 1;
   3, 1, 1;
   4, 2, 2, 1;
   5, 2, 2, 1, 1;
   6, 3, 2, 1, 2, 1;
   7, 3, 3, 1, 3, 1, 1;
   8, 4, 4, 2, 4, 2, 2, 1;
   9, 4, 4, 2, 4, 2, 2, 1, 1;
  10, 5, 4, 2, 4, 2, 2, 1, 2, 1;
  11, 5, 5, 2, 4, 2, 2, 1, 3, 1, 1;
  12, 6, 6, 3, 4, 2, 2, 1, 4, 2, 2, 1;
  13, 6, 6, 3, 5, 2, 2, 1, 5, 2, 2, 1, 1;
  ...
		

Crossrefs

Sums include: A006046 (row), A007729 (diagonal).

Programs

  • Magma
    A166556:= func< n,k | (&+[(Binomial(j,k) mod 2): j in [k..n]]) >;
    [A166556(n,k): k in [0..n], n in [0..15]]; // G. C. Greubel, Dec 02 2024
    
  • Maple
    A166556 := proc(n,k)
        local j;
        add(A047999(j,k),j=k..n) ;
    end proc: # R. J. Mathar, Jul 21 2016
  • Mathematica
    A166556[n_, k_]:= Sum[Mod[Binomial[j,k], 2], {j,k,n}];
    Table[A166556[n,k], {n,0,15}, {k,0,n}]//Flatten (* G. C. Greubel, Dec 02 2024 *)
  • Python
    def A166556(n,k): return sum(binomial(j,k)%2 for j in range(k,n+1))
    print(flatten([[A166556(n,k) for k in range(n+1)] for n in range(13)])) # G. C. Greubel, Dec 02 2024

Formula

Triangle read by rows, A000012 * A047999; where A000012 = an infinite lower triangular matrix with all 1's: [1; 1,1; 1,1,1;..]; and A047999 = Sierpinski's gasket.
The operation takes partial sums of Sierpinski's gasket terms, by columns.
From G. C. Greubel, Dec 02 2024: (Start)
T(n, k) = Sum_{j=k..n} (binomial(j,k) mod 2).
T(n, 0) = A000027(n+1).
T(n, 1) = A004526(n+1).
T(n, 2) = A004524(n+1).
T(2*n, n) = A080100(n).
Sum_{k=0..n} T(n, k) = A006046(n+1).
Sum_{k=0..n} (-1)^k*T(n, k) = A006046(floor(n/2)+1).
Sum_{k=0..floor(n/2)} T(n-k, k) = A007729(n). (End)
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