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 1-7 of 7 results.

A201272 Number of n X 3 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

1, 1, 4, 7, 14, 21, 41, 54, 86, 120, 168, 218, 307, 377, 496, 621, 776, 937, 1177, 1380, 1676, 1984, 2344, 2716, 3221, 3665, 4260, 4875, 5570, 6285, 7201, 8026, 9074, 10152, 11344, 12566, 14071, 15449, 17136, 18865, 20748, 22673, 24977, 27112, 29656, 32256, 35056
Offset: 0

Views

Author

R. H. Hardin, Nov 29 2011

Keywords

Examples

			Some solutions for n=5:
..0..0..0....0..0..0....0..0..1....0..0..0....0..0..1....0..0..2....0..0..1
..0..0..2....0..0..1....0..0..2....0..0..1....0..0..1....0..0..2....0..1..1
..1..1..2....1..1..2....0..1..2....1..1..1....0..1..2....0..1..2....0..1..2
..1..1..2....1..1..2....1..1..2....1..2..2....1..1..2....1..1..2....0..1..2
..1..2..2....2..2..2....1..2..2....2..2..2....2..2..2....1..1..2....2..2..2
		

Crossrefs

Column 3 of A201277.

Formula

a(n) = 2*a(n-2) + 2*a(n-3) - a(n-4) - 4*a(n-5) + 2*a(n-7) - 2*a(n-9) + 4*a(n-11) + a(n-12) - 2*a(n-13) - 2*a(n-14) + a(n-16).
G.f.: 1 + x*(1 + 4*x + 5*x^2 + 4*x^3 + 7*x^5 + 7*x^6 + 2*x^7 - x^8 + x^9 + 4*x^10 + x^11 - 2*x^12 - 2*x^13 + x^15) / ((1 - x)^5*(1 + x)^3*(1 - x + x^2)*(1 + x + x^2)^3). - Colin Barker, Mar 02 2018

Extensions

a(0)=1 prepended by Alois P. Heinz, Mar 18 2024

A201271 Number of n X 2 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

1, 3, 5, 4, 12, 16, 9, 27, 33, 16, 48, 56, 25, 75, 85, 36, 108, 120, 49, 147, 161, 64, 192, 208, 81, 243, 261, 100, 300, 320, 121, 363, 385, 144, 432, 456, 169, 507, 533, 196, 588, 616, 225, 675, 705, 256, 768, 800, 289, 867, 901, 324, 972, 1008, 361, 1083, 1121, 400, 1200
Offset: 0

Views

Author

R. H. Hardin, Nov 29 2011

Keywords

Examples

			Some solutions for n=5:
..0..1....0..1....0..0....0..0....0..0....0..0....0..0....0..1....0..1....0..0
..0..1....0..1....0..0....0..1....0..1....0..1....0..0....0..2....0..1....0..2
..0..1....0..1....1..2....1..1....1..1....1..2....1..1....0..2....0..2....1..2
..0..2....1..2....1..2....2..2....1..2....1..2....1..2....1..2....1..2....1..2
..2..2....2..2....1..2....2..2....2..2....2..2....2..2....1..2....2..2....1..2
		

Crossrefs

Column 2 of A201277.

Formula

a(n) = 3*a(n-3) -3*a(n-6) +a(n-9).
Subsequences for n modulo 3 = 1,2,0:
p=(n+2)/3: a(n) = 3*p^2
q=(n+1)/3: a(n) = 3*q^2 + 2*q
r=(n+0)/3: a(n) = r^2 + 2*r + 1.
G.f.: 1+x*(3 + 5*x + 4*x^2 + 3*x^3 + x^4 - 3*x^5 + x^8) / ((1 - x)^3*(1 + x + x^2)^3). - Colin Barker, May 22 2018

Extensions

a(0)=1 prepended by Alois P. Heinz, Mar 18 2024

A201273 Number of n X 4 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

1, 3, 12, 14, 85, 199, 143, 740, 1274, 759, 3416, 5312, 2746, 11628, 16676, 7946, 32164, 43438, 19713, 76321, 99347, 43137, 162566, 205231, 86351, 318364, 391600, 161089, 581578, 702330, 282904, 1006014, 1195239, 473473, 1662549, 1947164, 761467, 2641053, 3058967
Offset: 0

Views

Author

R. H. Hardin, Nov 29 2011

Keywords

Examples

			Some solutions for n=5
..0..0..0..1....0..0..0..2....0..0..0..0....0..0..0..1....0..0..1..1
..0..0..1..1....0..1..1..2....0..0..1..1....0..0..1..2....0..0..1..1
..0..0..1..2....0..1..1..2....0..1..2..2....0..1..2..2....0..0..2..2
..1..1..2..2....0..1..2..2....1..1..2..2....0..1..2..2....0..1..2..2
..2..2..2..2....0..1..2..2....1..1..2..2....1..1..2..2....1..1..2..2
		

Crossrefs

Column 4 of A201277.

Formula

a(n) = a(n-3) +2*a(n-6) +a(n-9) -4*a(n-12) -5*a(n-15) +4*a(n-18) +5*a(n-21) +a(n-24) -6*a(n-27) +6*a(n-33) -a(n-36) -5*a(n-39) -4*a(n-42) +5*a(n-45) +4*a(n-48) -a(n-51) -2*a(n-54) -a(n-57) +a(n-60).

Extensions

a(0)=1 prepended by Alois P. Heinz, Mar 18 2024

A201274 Number of n X 5 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

1, 3, 16, 21, 199, 556, 442, 2827, 5680, 3651, 19960, 35039, 19820, 96084, 151800, 78205, 354360, 525467, 255143, 1089594, 1531163, 707770, 2908481, 3937393, 1758805, 6976823, 9145189, 3964264, 15328243, 19618905, 8309214, 31406219, 39327693, 16320584, 60602426
Offset: 0

Views

Author

R. H. Hardin, Nov 29 2011

Keywords

Examples

			Some solutions for n=6
..0..0..0..0..0....0..0..0..0..2....0..0..0..0..0....0..0..0..0..0
..0..1..1..1..1....0..0..0..1..2....0..0..0..0..0....0..1..1..1..2
..0..1..1..1..2....0..0..0..1..2....1..1..1..2..2....0..1..1..2..2
..0..1..2..2..2....1..1..1..1..2....1..1..1..2..2....0..1..1..2..2
..0..1..2..2..2....1..1..2..2..2....1..1..1..2..2....0..1..1..2..2
..0..1..2..2..2....1..1..2..2..2....1..2..2..2..2....0..1..2..2..2
		

Crossrefs

Column 5 of A201277.

Extensions

a(0)=1 prepended by Alois P. Heinz, Mar 18 2024

A201275 Number of n X 6 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

1, 1, 9, 41, 143, 442, 1260, 3113, 7331, 15969, 32737, 63942, 120318, 216392, 377902, 640970, 1055829, 1699241, 2679576, 4132842, 6267048, 9345121, 13712218, 19841970, 28343579, 39963063, 55722233, 76873873, 104958237, 141966994, 190366323, 253040267, 333758897
Offset: 0

Views

Author

R. H. Hardin, Nov 29 2011

Keywords

Examples

			Some solutions for n=5:
  0 0 0 0 0 0   0 0 0 1 1 1   0 0 0 0 0 0   0 0 0 0 1 1
  0 0 1 1 1 1   0 0 0 1 1 1   0 0 0 1 1 1   0 0 0 1 1 1
  0 1 1 1 2 2   0 0 1 1 1 1   0 1 1 1 1 2   0 1 1 1 1 2
  0 1 1 1 2 2   0 2 2 2 2 2   1 1 1 2 2 2   0 1 2 2 2 2
  2 2 2 2 2 2   0 2 2 2 2 2   2 2 2 2 2 2   0 2 2 2 2 2
		

Crossrefs

Column 6 of A201277.

Extensions

a(0)=1 prepended by Alois P. Heinz, Mar 18 2024

A201276 Number of n X 7 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

1, 3, 27, 54, 740, 2827, 3113, 27008, 71704, 59070, 408600, 894812, 621910, 3704174, 7087046, 4373879, 23558696, 41171126, 23396689, 116650532, 190010902, 101247815, 476808796, 736407602, 373431803, 1678517670, 2482516953, 1208979602, 5235742304, 7477415626
Offset: 0

Views

Author

R. H. Hardin, Nov 29 2011

Keywords

Examples

			Some solutions for n=5
..0..0..0..0..0..1..2....0..0..0..0..0..0..2....0..0..0..0..0..0..1
..0..0..0..1..1..1..2....0..0..1..1..1..1..2....0..0..0..1..1..1..2
..0..0..0..1..1..1..2....0..1..1..1..2..2..2....0..0..0..1..1..2..2
..1..1..1..1..2..2..2....0..1..1..1..2..2..2....1..1..1..1..1..2..2
..1..2..2..2..2..2..2....0..1..1..2..2..2..2....1..2..2..2..2..2..2
		

Crossrefs

Column 7 of A201277.

Extensions

a(0)=1 prepended by Alois P. Heinz, Mar 18 2024

A201270 Number of n X n 0..2 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

1, 3, 5, 7, 85, 556, 1260, 27008, 215577, 613916, 16442049, 152673459, 487975060, 14392411292, 144918917509, 496264541787, 15559415313705, 165127072154120, 592098075114238, 19339952787547252, 212870280758956694, 788675446037414831, 26535438036570486429, 300014957716483809886
Offset: 0

Views

Author

R. H. Hardin, Nov 29 2011

Keywords

Examples

			Some solutions for n=5
..0..0..0..0..2....0..0..0..0..2....0..0..0..0..0....0..0..0..0..0
..0..0..1..2..2....0..0..1..1..2....0..0..0..1..1....0..0..1..2..2
..0..1..1..2..2....0..1..1..2..2....1..1..1..1..1....0..1..1..2..2
..0..1..1..2..2....0..1..1..2..2....1..2..2..2..2....1..1..1..2..2
..1..1..1..2..2....1..1..1..2..2....2..2..2..2..2....1..1..1..2..2
		

Crossrefs

Main diagonal of A201277.

Extensions

a(0)=1 prepended and a(19)-a(23) added by Alois P. Heinz, Mar 17 2024
Showing 1-7 of 7 results.