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 1-10 of 10 results.

A208103 Number of n X 3 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

6, 36, 78, 171, 406, 990, 2485, 6328, 16290, 42195, 109746, 286146, 747253, 1953276, 5108806, 13367035, 34982430, 91564278, 239684565, 627447600, 1642590586, 4300214691, 11257876378, 29473127866, 77161043541, 202009252500
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Column 3 of A208108.

Examples

			Some solutions for n=10:
..1..0..0....0..0..1....1..0..0....0..1..1....0..1..1....0..0..1....1..0..1
..0..0..1....1..0..0....0..0..1....0..0..1....0..0..1....0..1..1....1..0..1
..1..0..0....0..1..1....1..1..0....0..0..1....1..0..1....0..0..1....1..0..1
..0..1..1....1..0..0....0..0..1....0..1..1....0..1..1....1..1..1....1..0..1
..1..0..0....0..1..1....1..0..0....0..0..1....1..0..1....0..0..1....1..1..1
..0..1..1....1..0..0....0..0..1....0..0..1....0..0..1....0..1..1....1..0..1
..1..0..0....0..0..1....1..0..0....0..1..1....1..0..1....1..0..1....1..1..1
..0..0..1....1..0..0....0..0..1....1..0..1....0..0..1....0..1..1....1..0..1
..1..1..0....0..1..1....1..0..0....0..0..1....0..1..1....1..0..1....1..0..1
..0..0..1....1..0..0....0..0..1....0..0..1....0..0..1....0..1..1....1..0..1
		

Crossrefs

Cf. A208108.

Formula

Empirical: a(n) = 4*a(n-1) - 2*a(n-2) - 6*a(n-3) + 4*a(n-4) + 2*a(n-5) - a(n-6) for n>7.
Empirical g.f.: x*(6 + 12*x - 54*x^2 - 33*x^3 + 70*x^4 + 20*x^5 - 15*x^6) / ((1 - x)*(1 + x)*(1 - 3*x + x^2)*(1 - x - x^2)). - Colin Barker, Mar 06 2018

A208102 Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

2, 16, 78, 361, 6235, 261121, 4747545, 90782784, 18473477832, 9693564675601, 668167531935849, 46925086118316121, 128627682135940435023, 919037094400530117376144, 213624920267877921384329046
Offset: 1

Views

Author

R. H. Hardin Feb 23 2012

Keywords

Comments

Diagonal of A208108

Examples

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

A208104 Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

9, 81, 169, 361, 841, 2025, 5041, 12769, 32761, 84681, 219961, 573049, 1495729, 3908529, 10220809, 26739241, 69973225, 183142089, 479391025, 1254930625, 3285238489, 8600522121, 22515902809, 58946498521, 154322479921, 404019140625
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Column 4 of A208108.

Examples

			Some solutions for n=10:
..1..1..0..1....1..1..0..1....0..1..1..1....0..1..1..0....0..0..1..1
..0..1..1..1....1..1..0..0....0..1..1..0....0..1..1..1....1..1..1..0
..1..1..0..1....1..1..0..1....0..1..1..1....1..1..1..0....0..0..1..1
..0..1..1..1....1..1..0..0....0..1..1..0....0..1..1..0....0..1..1..0
..1..1..0..1....1..1..1..1....1..1..1..1....1..1..1..1....1..0..1..1
..0..1..1..1....1..1..0..0....0..1..1..0....0..1..1..0....0..1..1..0
..1..1..0..1....1..1..1..1....1..1..1..1....1..1..1..1....1..0..1..1
..0..1..1..1....1..1..0..0....0..1..1..0....0..1..1..0....0..1..1..0
..1..1..0..1....1..1..0..1....1..1..1..0....0..1..1..1....1..0..1..1
..0..1..1..1....1..1..0..0....0..1..1..0....1..1..1..0....0..1..1..0
		

Crossrefs

Cf. A208108.

Formula

Empirical: a(n) = 4*a(n-1) - 2*a(n-2) - 6*a(n-3) + 4*a(n-4) + 2*a(n-5) - a(n-6) for n>7.
Empirical g.f.: x*(9 + 45*x - 137*x^2 - 99*x^3 + 185*x^4 + 55*x^5 - 40*x^6) / ((1 - x)*(1 + x)*(1 - 3*x + x^2)*(1 - x - x^2)). - Colin Barker, Jun 28 2018

A208105 Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

15, 225, 611, 1805, 6235, 22995, 89815, 361261, 1483295, 6161925, 25792655, 108453119, 457324951, 1931799849, 8168996779, 34567178365, 146331546515, 619615536891, 2624066727095, 11113979515925, 47075003890759
Offset: 1

Views

Author

R. H. Hardin Feb 23 2012

Keywords

Comments

Column 5 of A208108

Examples

			Some solutions for n=7
..0..1..1..1..0....0..1..1..1..0....1..0..0..1..1....1..1..0..0..1
..1..1..0..0..1....0..0..1..1..0....1..0..1..1..0....0..0..1..1..0
..0..1..1..1..0....1..0..1..1..0....1..1..0..1..1....1..1..0..0..1
..1..1..0..0..1....0..1..1..1..0....1..0..1..1..0....0..0..1..1..0
..0..1..1..1..0....1..0..1..1..1....1..0..0..1..1....1..1..0..0..1
..1..1..0..0..1....0..1..1..1..0....1..1..1..1..0....0..0..1..1..0
..0..1..1..1..0....1..0..1..1..1....1..0..0..1..1....1..1..0..0..1
		

Formula

Empirical: a(n) = 7*a(n-1) -8*a(n-2) -27*a(n-3) +45*a(n-4) +24*a(n-5) -51*a(n-6) -3*a(n-7) +16*a(n-8) -a(n-9) -a(n-10) for n>11

A208106 Number of nX6 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

25, 625, 2209, 9025, 46225, 261121, 1600225, 10220809, 67158025, 448380625, 3024450025, 20525433289, 139828879969, 954796716769, 6529082812849, 44686751584225, 306015929742721, 2096314482667729, 14363485816713121
Offset: 1

Views

Author

R. H. Hardin Feb 23 2012

Keywords

Comments

Column 6 of A208108

Examples

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

Formula

Empirical: a(n) = 11*a(n-1) -17*a(n-2) -124*a(n-3) +276*a(n-4) +396*a(n-5) -902*a(n-6) -462*a(n-7) +946*a(n-8) +220*a(n-9) -340*a(n-10) -44*a(n-11) +39*a(n-12) +3*a(n-13) -a(n-14) for n>15

A208107 Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

40, 1600, 6016, 25555, 134160, 768544, 4747545, 30461016, 200679160, 1341923275, 9060096280, 61521142072, 419255546841, 2863417898992, 19583147331312, 134042927712195, 917974509748384, 6288633342628816, 43089144637765369
Offset: 1

Views

Author

R. H. Hardin Feb 23 2012

Keywords

Comments

Column 7 of A208108

Examples

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

Formula

Empirical: a(n) = 11*a(n-1) -17*a(n-2) -124*a(n-3) +276*a(n-4) +396*a(n-5) -902*a(n-6) -462*a(n-7) +946*a(n-8) +220*a(n-9) -340*a(n-10) -44*a(n-11) +39*a(n-12) +3*a(n-13) -a(n-14) for n>15

A208109 Number of 4 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

9, 81, 171, 361, 1805, 9025, 25555, 72361, 292941, 1185921, 3801699, 12187081, 45351581, 168766081, 570110035, 1925893225, 6923341485, 24888533121, 85943617731, 296775442441, 1051712556989, 3727058052481, 12988702493491
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Row 4 of A208108.

Examples

			Some solutions for n=8:
..0..1..1..1..0..1..1..1....1..0..1..1..1..0..1..1....0..1..1..1..1..1..1..1
..1..1..1..0..0..1..1..0....0..0..1..1..1..0..1..1....1..0..1..1..1..0..1..1
..0..1..1..0..0..1..1..1....0..0..1..1..1..1..1..1....0..0..1..1..1..0..1..1
..0..1..1..1..0..1..1..0....1..1..1..1..1..0..1..1....0..1..1..1..1..0..1..1
		

Crossrefs

Cf. A208108.

Formula

Empirical: a(n) = 2*a(n-1) + 8*a(n-3) + 61*a(n-4) - 66*a(n-5) - 48*a(n-6) - 252*a(n-8) + 216*a(n-9).
Empirical g.f.: x*(9 + 63*x + 9*x^2 - 53*x^3 - 114*x^4 - 300*x^5 - 36*x^6 - 36*x^7 + 216*x^8) / ((1 - 2*x - 7*x^2 + 6*x^3)*(1 + 7*x^2 - 12*x^4 - 36*x^6)). - Colin Barker, Jun 28 2018

A208110 Number of 5 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

14, 196, 406, 841, 6235, 46225, 134160, 389376, 2189616, 12313081, 42602769, 147403881, 722705166, 3543344676, 13461507270, 51141561025, 233619318395, 1067194368601, 4261393225856, 17016087003136, 74907424036224
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Row 5 of A208108.

Examples

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

Crossrefs

Cf. A208108.

Formula

Empirical: a(n) = 2*a(n-1) + 13*a(n-3) + 166*a(n-4) - 176*a(n-5) - 143*a(n-6) - 1452*a(n-8) + 1331*a(n-9).
Empirical g.f.: x*(14 + 168*x + 14*x^2 - 153*x^3 - 319*x^4 - 1595*x^5 - 121*x^6 - 121*x^7 + 1331*x^8) / ((1 - 2*x - 12*x^2 + 11*x^3)*(1 + 12*x^2 - 22*x^4 - 121*x^6)). - Colin Barker, Jun 28 2018

A208111 Number of 6 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

22, 484, 990, 2025, 22995, 261121, 768544, 2262016, 18608992, 153091129, 558232641, 2035543689, 13946476806, 95553937924, 397367788702, 1652481969121, 10150368975235, 62348632093225, 281328849436320, 1269409109197824
Offset: 1

Views

Author

R. H. Hardin, Feb 23 2012

Keywords

Comments

Row 6 of A208108.

Examples

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

Crossrefs

Cf. A208108.

Formula

Empirical: a(n) = 2*a(n-1) + 21*a(n-3) + 438*a(n-4) - 456*a(n-5) - 399*a(n-6) - 7220*a(n-8) + 6859*a(n-9).
Empirical g.f.: x*(22 + 440*x + 22*x^2 - 417*x^3 - 855*x^4 - 7619*x^5 - 361*x^6 - 361*x^7 + 6859*x^8) / ((1 - 2*x - 20*x^2 + 19*x^3)*(1 + 20*x^2 - 38*x^4 - 361*x^6)). - Colin Barker, Jun 28 2018

A208112 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 1 0 vertically.

Original entry on oeis.org

35, 1225, 2485, 5041, 89815, 1600225, 4747545, 14085009, 176312187, 2207026441, 8330645133, 31444864929, 316504755855, 3185743068225, 14132905548945, 62697780385249, 546849942762131, 4769624348126089, 23640747042219941
Offset: 1

Views

Author

R. H. Hardin Feb 23 2012

Keywords

Comments

Row 7 of A208108

Examples

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

Formula

Empirical: a(n) = 2*a(n-1) +34*a(n-3) +1153*a(n-4) -1184*a(n-5) -1088*a(n-6) -33792*a(n-8) +32768*a(n-9)
Showing 1-10 of 10 results.