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 1-9 of 9 results.

A208063 Number of n X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

2, 16, 72, 576, 3696, 26244, 198000, 1638400, 12913840, 117722500, 1052059680, 10059287616, 97769309736, 1020075760144, 10507456855392, 116747852120064, 1295601058976256, 15148523442518244, 177995312325281880
Offset: 1

Views

Author

R. H. Hardin Feb 23 2012

Keywords

Comments

Diagonal of A208069

Examples

			Some solutions for n=4
..1..0..1..1....1..0..0..1....1..1..0..1....1..0..0..1....1..1..0..1
..0..0..1..1....1..1..0..1....1..1..0..1....0..1..1..0....0..1..0..1
..0..0..1..1....1..0..0..1....1..1..0..1....1..0..0..1....1..0..0..1
..0..0..1..1....1..0..0..1....1..0..0..1....0..1..1..0....0..1..0..1
		

A208064 Number of n X 3 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

6, 36, 72, 144, 216, 324, 432, 576, 720, 900, 1080, 1296, 1512, 1764, 2016, 2304, 2592, 2916, 3240, 3600, 3960, 4356, 4752, 5184, 5616, 6084, 6552, 7056, 7560, 8100, 8640, 9216, 9792, 10404, 11016, 11664, 12312, 12996, 13680, 14400, 15120, 15876, 16632
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Column 3 of A208069.

Examples

			Some solutions for n=4:
..0..0..1....1..1..0....1..1..0....0..1..1....1..1..0....0..0..1....0..0..1
..0..1..1....1..0..1....1..1..0....1..1..0....0..0..1....0..1..1....0..0..1
..0..0..1....1..0..0....1..0..0....0..1..1....1..1..0....0..0..1....0..0..1
..0..0..1....0..0..1....1..1..0....1..0..0....0..0..1....0..1..0....0..0..1
		

Crossrefs

Cf. A208069.

Formula

Empirical: a(n) = 2*a(n-1) - 2*a(n-3) + a(n-4) for n>5.
Conjectures from Colin Barker, Jun 27 2018: (Start)
G.f.: 6*x*(1 + 4*x + 2*x^3 - x^4) / ((1 - x)^3*(1 + x)).
a(n) = 9*n^2 for n>1 and even.
a(n) = 9*n^2-9 for n>1 and odd.
(End)

A208065 Number of n X 4 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

10, 100, 240, 576, 1008, 1764, 2688, 4096, 5760, 8100, 10800, 14400, 18480, 23716, 29568, 36864, 44928, 54756, 65520, 78400, 92400, 108900, 126720, 147456, 169728, 195364, 222768, 254016, 287280, 324900, 364800, 409600, 456960, 509796, 565488
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Column 4 of A208069.

Examples

			Some solutions for n=4:
..0..1..1..0....1..1..0..1....0..1..0..0....0..0..1..0....1..1..0..1
..1..1..0..1....0..0..1..0....0..0..1..0....1..1..0..0....1..1..0..1
..0..1..0..0....0..1..0..1....0..1..0..0....0..0..1..0....1..1..0..1
..1..0..0..1....0..0..1..0....0..0..1..0....1..1..0..0....1..0..0..1
		

Crossrefs

Cf. A208069.

Formula

Empirical: a(n) = 2*a(n-1) + 2*a(n-2) - 6*a(n-3) + 6*a(n-5) - 2*a(n-6) - 2*a(n-7) + a(n-8) for n>9.
Conjectures from Colin Barker, Jun 27 2018: (Start)
G.f.: 2*x*(5 + 40*x + 10*x^2 - 22*x^3 - 12*x^4 - 12*x^5 + 10*x^6 + 10*x^7 - 5*x^8) / ((1 - x)^5*(1 + x)^3).
a(n) = n^2*(n + 8)^2/4 for n>1 and even.
a(n) = (n - 1)*(n + 1)*(n + 7)*(n + 9)/4 for n>1 and odd.
(End)

A208066 Number of n X 5 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

16, 256, 704, 1936, 3696, 7056, 11424, 18496, 27200, 40000, 55200, 76176, 100464, 132496, 168896, 215296, 267264, 331776, 403200, 490000, 585200, 698896, 822624, 968256, 1125696, 1308736, 1505504, 1731856, 1974000, 2250000, 2544000, 2876416
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Column 5 of A208069.

Examples

			Some solutions for n=4.
..1..0..1..1..0....1..1..0..0..1....1..1..0..1..1....0..0..1..0..0
..0..0..1..0..1....1..0..1..1..0....0..0..1..0..1....1..1..0..0..1
..0..0..1..0..0....1..1..0..0..1....0..1..0..1..0....0..0..1..0..0
..0..0..1..0..1....0..0..1..1..0....0..0..1..0..1....0..1..0..0..1
		

Crossrefs

Cf. A208069.

Formula

Empirical: a(n) = 2*a(n-1) + 2*a(n-2) - 6*a(n-3) + 6*a(n-5) - 2*a(n-6) - 2*a(n-7) + a(n-8) for n>9.
Empirical g.f.: 16*x*(1 + 14*x + 10*x^2 + 7*x^3 - 3*x^4 - 5*x^5 + 2*x^6 + 2*x^7 - x^8) / ((1 - x)^5*(1 + x)^3). - Colin Barker, Jun 27 2018

A208067 Number of n X 6 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

26, 676, 2080, 6400, 12960, 26244, 44064, 73984, 111520, 168100, 236160, 331776, 443520, 592900, 763840, 984064, 1232064, 1542564, 1887840, 2310400, 2775520, 3334276, 3944160, 4665600, 5447520, 6360484, 7344064, 8479744, 9696960
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Column 6 of A208069.

Examples

			Some solutions for n=4:
..0..1..1..0..0..1....0..0..1..0..0..1....1..1..0..1..1..0....0..1..1..0..0..1
..1..0..0..1..1..0....1..1..0..0..1..0....1..0..1..1..0..1....1..0..0..1..1..0
..0..0..1..0..0..1....0..0..1..0..0..1....0..1..0..0..1..0....0..1..1..0..0..1
..1..0..0..1..0..0....0..1..0..0..1..0....1..0..1..0..0..1....1..0..0..1..0..0
		

Crossrefs

Cf. A208069.

Formula

Empirical: a(n) = 2*a(n-1) + 2*a(n-2) - 6*a(n-3) + 6*a(n-5) - 2*a(n-6) - 2*a(n-7) + a(n-8) for n>9.
Empirical g.f.: 2*x*(13 + 312*x + 338*x^2 + 522*x^3 + 28*x^4 - 76*x^5 + 26*x^6 + 26*x^7 - 13*x^8) / ((1 - x)^5*(1 + x)^3). - Colin Barker, Jun 27 2018

A208068 Number of n X 7 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

42, 1764, 6216, 21904, 48840, 108900, 198000, 360000, 582000, 940900, 1408440, 2108304, 2988216, 4235364, 5762400, 7840000, 10332000, 13616100, 17490600, 22467600, 28259880, 35545444, 43928016, 54287424, 66090960, 80460900, 96696600
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Column 7 of A208069.

Examples

			Some solutions for n=4:
..1..1..0..0..1..1..0....1..0..1..0..1..0..1....0..0..1..0..1..1..0
..0..1..1..0..1..1..0....0..1..0..1..1..0..1....0..0..1..1..0..1..1
..0..1..0..0..1..1..0....0..0..1..0..1..0..1....0..0..1..0..0..1..0
..0..0..1..0..0..1..0....0..1..0..1..1..0..0....0..0..1..0..0..1..0
		

Crossrefs

Cf. A208069.

Formula

Empirical: a(n) = 2*a(n-1) + 4*a(n-2) - 10*a(n-3) - 5*a(n-4) + 20*a(n-5) - 20*a(n-7) + 5*a(n-8) + 10*a(n-9) - 4*a(n-10) - 2*a(n-11) + a(n-12) for n>13.
Empirical g.f.: 2*x*(21 + 840*x + 1260*x^2 + 1418*x^3 - 991*x^4 - 3128*x^5 - 160*x^6 + 1420*x^7 + 95*x^8 - 160*x^9 + 84*x^10 + 42*x^11 - 21*x^12) / ((1 - x)^7*(1 + x)^5). - Colin Barker, Jun 27 2018

A208070 Number of 5 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

12, 144, 216, 1008, 3696, 12960, 48840, 179520, 657000, 2423280, 8913456, 32769360, 120581784, 443565696, 1631571912, 6002079552, 22079078352, 81218792016, 298770650040, 1099049754720, 4042930839192, 14872226620512, 54708578740752
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Row 5 of A208069.

Examples

			Some solutions for n=4:
..0..0..1..1....1..1..0..0....1..1..0..1....0..0..1..1....0..1..1..0
..0..1..0..0....0..0..1..1....1..1..0..1....0..1..0..0....1..1..0..1
..0..0..1..1....1..1..0..0....1..1..0..1....0..0..1..1....0..1..0..0
..0..1..0..0....0..0..1..1....1..1..0..1....0..1..0..0....1..0..0..1
..0..0..1..1....0..1..0..0....0..1..0..1....0..0..1..0....0..1..0..0
		

Crossrefs

Cf. A208069.

Formula

Empirical: a(n) = a(n-1) + 4*a(n-2) + 19*a(n-3) + 10*a(n-4) + 5*a(n-5) - 27*a(n-6) - 2*a(n-7) - 4*a(n-8) + 8*a(n-9) for n>11.
Empirical g.f.: 12*x*(1 + 11*x + 2*x^2 - x^3 - 86*x^4 - 31*x^5 - 51*x^6 + 114*x^7 + 4*x^8 + 24*x^9 - 32*x^10) / ((1 - 2*x - 4*x^2 - 8*x^3)*(1 + x + 2*x^2 - 3*x^3 - x^5 + x^6)). - Colin Barker, Jun 27 2018

A208071 Number of 6 X n 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

16, 256, 324, 1764, 7056, 26244, 108900, 435600, 1726596, 6937956, 27751824, 110880900, 443776356, 1775105424, 7099410564, 28399664484, 113598657936, 454386542724, 1817562348900, 7270249395600, 29080932870276, 116323860905316
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Row 6 of A208069.

Examples

			Some solutions for n=4:
..0..1..0..1....1..0..1..1....1..0..0..1....0..0..1..1....1..0..0..1
..0..0..1..0....0..1..0..0....0..1..1..0....0..1..0..0....0..1..1..0
..0..1..0..1....0..0..1..1....1..0..0..1....0..0..1..1....1..0..0..1
..0..0..1..0....0..1..0..0....0..1..1..0....0..1..0..0....0..0..1..0
..0..1..0..0....0..0..1..0....1..0..0..1....0..0..1..1....1..0..0..1
..0..0..1..0....0..1..0..0....0..0..1..0....0..1..0..0....0..0..1..0
		

Crossrefs

Cf. A208069.

Formula

Empirical: a(n) = 2*a(n-1) + 4*a(n-2) + 17*a(n-3) - 2*a(n-4) - 4*a(n-5) - 16*a(n-6) for n>8.
Empirical g.f.: 4*x*(4 + 56*x - 63*x^2 - 45*x^3 - 522*x^4 + 36*x^5 + 32*x^6 + 448*x^7) / ((1 - x)*(1 - 4*x)*(1 + x + x^2)*(1 + 2*x + 4*x^2)). - Colin Barker, Jun 27 2018

A208072 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.

Original entry on oeis.org

20, 400, 432, 2688, 11424, 44064, 198000, 844800, 3542544, 15213984, 64859616, 275633280, 1175819856, 5010674496, 21340192176, 90942560256, 387500834976, 1650940063776, 7034502996720, 29972774288640, 127706156346384
Offset: 1

Views

Author

R. H. Hardin Feb 23 2012

Keywords

Comments

Row 7 of A208069

Examples

			Some solutions for n=4
..1..1..0..1....1..0..0..1....1..1..0..1....0..0..1..0....1..1..0..1
..1..1..0..1....0..1..1..0....1..0..0..1....0..0..1..1....1..1..0..1
..1..1..0..1....1..0..0..1....1..1..0..0....0..0..1..0....0..1..0..0
..0..1..0..1....0..1..1..0....1..0..0..1....0..0..1..0....1..0..0..1
..1..1..0..0....1..0..0..1....0..1..0..0....0..0..1..0....0..1..0..0
..0..1..0..1....0..0..1..0....1..0..0..1....0..0..1..0....1..0..0..1
..0..1..0..0....1..0..0..1....0..1..0..0....0..0..1..0....0..1..0..0
		

Formula

Empirical: a(n) = a(n-1) +4*a(n-2) +39*a(n-3) +20*a(n-4) +19*a(n-5) -191*a(n-6) -42*a(n-7) -36*a(n-8) +216*a(n-9) for n>11
Showing 1-9 of 9 results.