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 13 results. Next

A281050 Number of n X 2 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 1, 6, 29, 122, 468, 1686, 5807, 19338, 62731, 199264, 622152, 1914780, 5821645, 17515566, 52221929, 154461110, 453654108, 1324053522, 3842768987, 11096398578, 31895230903, 91296545404, 260329675536, 739725018360, 2095147333465
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Examples

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

Crossrefs

Column 2 of A281056.

Formula

Empirical: a(n) = 9*a(n-1) - 30*a(n-2) + 45*a(n-3) - 30*a(n-4) + 9*a(n-5) - a(n-6).
Empirical g.f.: x^2*(1 - 3*x + 5*x^2 - 4*x^3) / (1 - 3*x + x^2)^3. - Colin Barker, Feb 15 2019

A281051 Number of n X 3 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 6, 68, 376, 1492, 4988, 15028, 42252, 113076, 291660, 731060, 1791052, 4306868, 10197068, 23828404, 55060556, 125999028, 285894732, 643864500, 1440442444, 3203438516, 7086237772, 15599703988, 34190878796, 74638727092, 162339448908
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Examples

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

Crossrefs

Column 3 of A281056.

Formula

Empirical: a(n) = 5*a(n-1) - 6*a(n-2) - 4*a(n-3) + 8*a(n-4) for n>6.
Empirical g.f.: 2*x^2*(3 + x)*(1 + 2*x)*(1 + 4*x + 2*x^2) / ((1 + x)*(1 - 2*x)^3). - Colin Barker, Feb 15 2019

A281052 Number of nX4 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

1, 34, 239, 1022, 3416, 10112, 27635, 71419, 177320, 426696, 1002035, 2306828, 5224307, 11669686, 25762564, 56301813, 121961820, 262154625, 559637795, 1187392495, 2505484374, 5260557953, 10995496220, 22888340830, 47465895442
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Column 4 of A281056.

Examples

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

Crossrefs

Cf. A281056.

Formula

Empirical: a(n) = 3*a(n-1) +3*a(n-2) -11*a(n-3) -9*a(n-4) +18*a(n-5) +17*a(n-6) -12*a(n-7) -15*a(n-8) +3*a(n-9) +6*a(n-10) -a(n-12) for n>14

A281053 Number of nX5 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

2, 104, 618, 2452, 7803, 22106, 58005, 144283, 344972, 800225, 1812024, 4023754, 8791481, 18948288, 40366695, 85135873, 177990242, 369259703, 760850914, 1558181104, 3173635543, 6432024694, 12977428633, 26076680087, 52202242904
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Column 5 of A281056.

Examples

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

Crossrefs

Cf. A281056.

Formula

Empirical: a(n) = 5*a(n-1) -6*a(n-2) -4*a(n-3) +5*a(n-4) +9*a(n-5) -12*a(n-7) -3*a(n-8) +3*a(n-9) +6*a(n-10) -a(n-12) -a(n-13) for n>16

A281054 Number of nX6 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

6, 251, 1403, 5400, 16875, 46610, 119205, 288527, 671451, 1515524, 3339671, 7217269, 15347530, 32196671, 66765699, 137073842, 278977066, 563443975, 1130260537, 2253558987, 4468793135, 8818038639, 17322550753, 33890757331
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Column 6 of A281056.

Examples

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

Crossrefs

Cf. A281056.

Formula

Empirical: a(n) = 3*a(n-1) +3*a(n-2) -11*a(n-3) -9*a(n-4) +15*a(n-5) +20*a(n-6) +3*a(n-7) -18*a(n-8) -27*a(n-9) -9*a(n-10) +15*a(n-11) +20*a(n-12) +12*a(n-13) -7*a(n-15) -6*a(n-16) -3*a(n-17) -a(n-18) for n>21

A281055 Number of nX7 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

13, 535, 2828, 10570, 32370, 87995, 221212, 526340, 1201939, 2661939, 5752796, 12190173, 25413086, 52258597, 106216045, 213723050, 426288170, 843735147, 1658596579, 3240610144, 6297012052, 12175728717, 23437264280, 44930659786
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Column 7 of A281056.

Examples

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

Crossrefs

Cf. A281056.

Formula

Empirical: a(n) = 5*a(n-1) -6*a(n-2) -4*a(n-3) +5*a(n-4) +9*a(n-5) -3*a(n-6) -3*a(n-7) -3*a(n-8) -9*a(n-9) +6*a(n-11) +8*a(n-12) +2*a(n-13) +3*a(n-14) -3*a(n-15) -3*a(n-16) -3*a(n-17) -a(n-18) -a(n-19) for n>23

A281057 Number of 2 X n 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 1, 6, 34, 104, 251, 535, 1076, 2090, 3956, 7353, 13474, 24417, 43846, 78142, 138374, 243687, 427098, 745403, 1296072, 2246018, 3880504, 6686165, 11491746, 19706373, 33722458, 57596214, 98195818, 167136611, 284039674, 482013727, 816869276
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Examples

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

Crossrefs

Row 2 of A281056.

Formula

Empirical: a(n) = 5*a(n-1) - 7*a(n-2) - 2*a(n-3) + 10*a(n-4) - 2*a(n-5) - 5*a(n-6) + a(n-7) + a(n-8) for n>14.
Empirical g.f.: x^2*(1 + x + 11*x^2 - 22*x^3 - 29*x^4 + 18*x^5 + 43*x^6 + 14*x^7 - 31*x^8 - 13*x^9 + 8*x^10 + 2*x^11 - x^12) / ((1 - x)^2*(1 - x - x^2)^3). - Colin Barker, Feb 15 2019

A281058 Number of 3 X n 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 6, 68, 239, 618, 1403, 2828, 5482, 10342, 19136, 34907, 62976, 112617, 199929, 352771, 619208, 1081946, 1882951, 3265367, 5644772, 9730124, 16728760, 28693405, 49108842, 83882613, 143016171, 243420929, 413658928, 701916100, 1189400585
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Examples

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

Crossrefs

Row 3 of A281056.

Formula

Empirical: a(n) = 5*a(n-1) - 7*a(n-2) - 2*a(n-3) + 10*a(n-4) - 2*a(n-5) - 5*a(n-6) + a(n-7) + a(n-8) for n>15.
Empirical g.f.: x^2*(6 + 38*x - 59*x^2 - 89*x^3 + 62*x^4 - 51*x^5 + 175*x^6 + 166*x^7 - 217*x^8 - 106*x^9 + 71*x^10 + 21*x^11 - 7*x^12 - x^13) / ((1 - x)^2*(1 - x - x^2)^3). - Colin Barker, Feb 15 2019

A281059 Number of 4Xn 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 29, 376, 1022, 2452, 5400, 10570, 19892, 36616, 66354, 118926, 211382, 373266, 655580, 1146156, 1995858, 3463242, 5990498, 10332426, 17775144, 30506480, 52242450, 89285638, 152311246, 259377954, 440998484, 748670868, 1269219570
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Row 4 of A281056.

Examples

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

Crossrefs

Cf. A281056.

Formula

Empirical: a(n) = 6*a(n-1) -12*a(n-2) +5*a(n-3) +12*a(n-4) -12*a(n-5) -3*a(n-6) +6*a(n-7) -a(n-9) for n>17

A281060 Number of 5Xn 0..1 arrays with no element equal to more than one of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.

Original entry on oeis.org

0, 122, 1492, 3416, 7803, 16875, 32370, 59669, 107693, 191953, 339219, 595824, 1041681, 1814253, 3149435, 5451162, 9409735, 16202663, 27835100, 47716151, 81633286, 139397983, 237621979, 404396106, 687167939, 1165993033, 1975805797
Offset: 1

Views

Author

R. H. Hardin, Jan 13 2017

Keywords

Comments

Row 5 of A281056.

Examples

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

Crossrefs

Cf. A281056.

Formula

Empirical: a(n) = 6*a(n-1) -12*a(n-2) +5*a(n-3) +12*a(n-4) -12*a(n-5) -3*a(n-6) +6*a(n-7) -a(n-9) for n>18
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