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 1-3 of 3 results.

A185781 Accumulation array of A185780, by antidiagonals.

Original entry on oeis.org

1, 5, 2, 14, 12, 3, 30, 36, 21, 4, 55, 80, 66, 32, 5, 91, 150, 150, 104, 45, 6, 140, 252, 285, 240, 150, 60, 7, 204, 392, 483, 460, 350, 204, 77, 8, 285, 576, 756, 784, 675, 480, 266, 96, 9, 385, 810, 1116, 1232, 1155, 930, 630, 336, 117, 10, 506, 1100, 1575, 1824, 1820, 1596, 1225, 800, 414, 140, 11, 650, 1452, 2145, 2580, 2700, 2520, 2107, 1560, 990, 500, 165, 12
Offset: 1

Views

Author

Clark Kimberling, Feb 03 2011

Keywords

Comments

See A144112 and A185780.

Examples

			Northwest corner:
1.....5....14....30....55
2.....12...36....80....150
3.....21...66....150...285
4.....32...104...240...460
5.....45...150...350...675
		

Crossrefs

Columns 1 to 4: A000027, A028347, 2*A033537, 10*A005563.

Programs

  • Mathematica
    (See A185780.)
    f[n_, k_] := k*(k + 1)*n*(k*n - n + k + 2)/6; Table[f[n - k + 1, k], {n, 10}, {k, n, 1, -1}] // Flatten (* G. C. Greubel, Jul 12 2017 *)

Formula

T(n,k) = k*(k+1)*n*(k*n-n+k+2)/6, k>=1, n>=1.

A185783 Second accumulation array of A185780, by antidiagonals.

Original entry on oeis.org

1, 6, 3, 20, 20, 6, 50, 70, 44, 10, 105, 180, 160, 80, 15, 196, 385, 420, 300, 130, 21, 336, 728, 910, 800, 500, 196, 28, 540, 1260, 1736, 1750, 1350, 770, 280, 36, 825, 2040, 3024, 3360, 2975, 2100, 1120, 384, 45, 1210, 3135, 4920, 5880, 5740, 4655, 3080, 1560, 510, 55, 1716, 4620, 7590, 9600, 10080, 9016, 6860, 4320, 2100, 660, 66, 2366, 6578, 11220, 14850, 16500, 15876, 13328, 9660, 5850, 2750, 836, 78
Offset: 1

Views

Author

Clark Kimberling, Feb 03 2011

Keywords

Comments

See A144112 and A185780.

Examples

			Northwest corner:
1....6....20....50....105
3....20...70....180...385
6....44...160...420...910
10...80...300...800...1750
		

Crossrefs

Row 1: A002415 (4-dimensional pyramidal numbers).
Columns 1 to 3: A000217, 2*A006503, 10*A005581.

Programs

  • Mathematica
    (See A185780.)
    f[n_, k_] := Binomial[k + 2, 3]*Binomial[n + 1, 2]*(k*n - n + 2*k + 4)/6; Table[f[n - k + 1, k], {n, 10}, {k, n, 1, -1}] // Flatten (* G. C. Greubel, Jul 12 2017 *)

Formula

T(n,k) = C(k+2,3)*C(n+1,2)*(k*n-n+2*k+4)/6, k>=1, n>=1.

A185782 Weight array of A185780, by antidiagonals.

Original entry on oeis.org

1, 3, 0, 5, 2, 0, 7, 4, 2, 0, 9, 6, 4, 2, 0, 11, 8, 6, 4, 2, 0, 13, 10, 8, 6, 4, 2, 0, 15, 12, 10, 8, 6, 4, 2, 0, 17, 14, 12, 10, 8, 6, 4, 2, 0, 19, 16, 14, 12, 10, 8, 6, 4, 2, 0, 21, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0, 23, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0, 25, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0, 27, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0
Offset: 1

Views

Author

Clark Kimberling, Feb 03 2011

Keywords

Examples

			Northwest corner:
1....3....5....7....9....11....13
0....2....4....6....8....10....12
0....2....4....6....8....10....12
(row n)=(row n-1) for n>=3.
		

Crossrefs

Programs

Showing 1-3 of 3 results.