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 1-8 of 8 results.

A204678 Number of n X 1 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..3 introduced in row major order.

Original entry on oeis.org

1, 2, 4, 12, 40, 143, 528, 1979, 7466, 28246, 106992, 405481, 1537042, 5826959, 22091016, 83752328, 317527448, 1203835147, 4564081020, 17303737555, 65603438014, 248721498050, 942974761824, 3575088704597, 13554190277870
Offset: 1

Views

Author

R. H. Hardin, Jan 18 2012

Keywords

Comments

Column 1 of A204685.

Examples

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

Formula

Empirical: a(n) = 4*a(n-1) + a(n-2) - 6*a(n-3) - 3*a(n-4) for n>6.
Empirical g.f.: x*(1 + x)*(1 - 3*x - 2*x^2 + 2*x^3 + x^4) / ((1 - x - x^2)*(1 - 3*x - 3*x^2)). - Colin Barker, Feb 19 2018

A204679 Number of n X 2 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..3 introduced in row major order.

Original entry on oeis.org

2, 15, 159, 2191, 31168, 447343, 6427791, 92387812, 1327953799, 19087798375, 274365294336, 3943689122935, 56686048473223, 814797524429284, 11711788424726319, 168343648648695295, 2419748633865949120
Offset: 1

Views

Author

R. H. Hardin, Jan 18 2012

Keywords

Comments

Column 2 of A204685.

Examples

			Some solutions for n=5:
..0..1....0..0....0..1....0..0....0..0....0..0....0..0....0..0....0..1....0..0
..1..0....1..0....1..0....0..1....0..0....0..0....0..0....0..0....0..1....0..0
..0..0....0..1....0..0....1..2....1..2....1..1....1..1....1..2....1..0....1..1
..0..1....1..0....2..1....0..1....1..3....2..3....0..1....2..1....1..0....1..2
..1..0....0..1....0..2....0..0....2..0....3..0....1..2....1..0....2..3....2..0
		

Crossrefs

Cf. A204685.

Formula

Empirical: a(n) = 14*a(n-1) +14*a(n-2) -124*a(n-3) -6*a(n-4) +90*a(n-5) -27*a(n-6) for n>8.
Empirical g.f.: x*(2 - 13*x - 79*x^2 + 3*x^3 + 140*x^4 - 57*x^5 - 21*x^6 + 9*x^7) / ((1 + x)*(1 + 3*x)*(1 - 3*x + x^2)*(1 - 15*x + 9*x^2)). - Colin Barker, Feb 23 2018

A204680 Number of nX3 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..3 introduced in row major order.

Original entry on oeis.org

4, 159, 6451, 287379, 12711292, 563046972, 24932875448, 1104148318540, 48896363697435, 2165344586789384, 95890854634053213, 4246463765107286355, 188051863862618823831, 8327753561924846574597, 368789108809170527549222
Offset: 1

Views

Author

R. H. Hardin Jan 18 2012

Keywords

Comments

Column 3 of A204685

Examples

			Some solutions for n=5
..0..1..1....0..0..1....0..0..1....0..0..1....0..0..1....0..0..1....0..0..1
..0..0..1....2..1..2....0..1..0....0..0..1....0..0..1....2..3..1....2..2..1
..2..0..2....2..3..0....2..3..3....1..2..2....1..2..2....1..1..3....0..3..2
..2..1..1....1..3..2....0..1..0....3..2..2....0..1..3....3..3..1....2..0..2
..3..1..0....1..1..2....1..2..1....3..3..1....1..3..3....0..1..1....3..3..1
		

Formula

Empirical: a(n) = 33*a(n-1) +576*a(n-2) -2576*a(n-3) -38824*a(n-4) +127580*a(n-5) +909748*a(n-6) -3116838*a(n-7) -7687952*a(n-8) +37104276*a(n-9) -63026296*a(n-10) -432695012*a(n-11) +2720629849*a(n-12) -5107909211*a(n-13) +3025539132*a(n-14) +16236494388*a(n-15) -61214998652*a(n-16) +60381991332*a(n-17) +26465066916*a(n-18) -101087636628*a(n-19) +92416374336*a(n-20) +14995740528*a(n-21) -85493406672*a(n-22) +58756380048*a(n-23) +4342368528*a(n-24) -38953846080*a(n-25) +13150955232*a(n-26) +1077909120*a(n-27) -6291032832*a(n-28) +3193509888*a(n-29) +1854296064*a(n-30) for n>33

A204681 Number of nX4 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..3 introduced in row major order.

Original entry on oeis.org

12, 2191, 287379, 40919141, 5770321516, 815364171994, 115180678788869, 16271532972153414, 2298647402512667451, 324726122304981135405, 45873499136412060284740, 6480470930161792394441041
Offset: 1

Views

Author

R. H. Hardin Jan 18 2012

Keywords

Comments

Column 4 of A204685

Examples

			Some solutions for n=5
..0..0..1..2....0..0..1..0....0..0..1..0....0..0..1..2....0..0..1..1
..0..1..2..1....1..1..2..0....1..0..1..0....1..2..1..1....0..0..2..0
..2..3..1..2....2..0..1..1....0..1..2..2....3..2..0..3....3..1..2..0
..0..2..2..3....2..0..2..2....2..3..2..2....3..0..1..3....3..1..1..2
..2..0..0..1....1..1..3..2....3..1..1..3....2..1..1..2....0..2..0..2
		

A204677 Number of n X n 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..3 introduced in row major order.

Original entry on oeis.org

1, 15, 6451, 40919141, 2579588216958
Offset: 1

Views

Author

R. H. Hardin, Jan 18 2012

Keywords

Comments

Diagonal of A204685.

Examples

			Some solutions for n=5
..0..1..1..0..2....0..0..1..1..0....0..0..1..0..2....0..0..1..0..0
..2..3..1..3..3....2..0..3..3..0....2..1..1..3..2....0..2..3..1..1
..0..0..3..2..3....2..3..1..0..3....0..1..0..3..3....2..0..1..0..0
..3..2..0..1..2....0..3..2..1..0....2..2..3..2..0....0..0..3..0..1
..0..3..3..1..2....2..2..3..0..0....1..0..3..3..2....1..2..1..3..2
		

Crossrefs

Cf. A204685.

A204682 Number of n X 5 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..3 introduced in row major order.

Original entry on oeis.org

40, 31168, 12711292, 5770321516, 2579588216958, 1155411237719424, 517329649988490420, 231643442002878488571
Offset: 1

Views

Author

R. H. Hardin, Jan 18 2012

Keywords

Examples

			Some solutions for n=5:
..0..0..1..0..1....0..0..1..0..0....0..1..0..0..1....0..1..1..0..2
..0..1..0..0..1....1..0..1..2..1....1..0..2..2..0....1..1..2..0..3
..2..3..0..3..0....1..1..2..1..0....2..2..1..1..0....2..3..3..1..0
..2..1..1..0..3....3..3..0..1..3....1..1..2..2..1....2..1..3..2..0
..3..0..2..3..2....0..1..0..2..3....0..0..3..0..0....1..0..2..0..1
		

Crossrefs

Column 5 of A204685.

A204683 Number of nX6 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..3 introduced in row major order.

Original entry on oeis.org

143, 447343, 563046972, 815364171994, 1155411237719424
Offset: 1

Views

Author

R. H. Hardin Jan 18 2012

Keywords

Comments

Column 6 of A204685

Examples

			Some solutions for n=5
..0..0..1..1..2..2....0..0..1..0..0..2....0..0..1..0..0..1....0..1..0..0..2..2
..0..1..3..1..3..1....1..1..0..0..3..1....1..2..1..0..1..3....0..2..3..3..0..1
..2..3..2..2..3..2....3..1..3..1..3..2....1..3..3..2..0..1....2..3..2..3..1..1
..0..2..1..1..2..1....2..2..3..3..2..0....0..0..1..1..3..3....1..3..3..0..1..3
..3..2..3..1..0..0....1..0..0..3..1..3....0..3..1..1..3..2....1..0..3..0..2..1
		

A204684 Number of nX7 0..3 arrays with no occurrence of three equal elements in a row horizontally, vertically, diagonally or antidiagonally, and new values 0..3 introduced in row major order.

Original entry on oeis.org

528, 6427791, 24932875448, 115180678788869, 517329649988490420
Offset: 1

Views

Author

R. H. Hardin Jan 18 2012

Keywords

Comments

Column 7 of A204685

Examples

			Some solutions for n=5
..0..1..1..0..0..2..3....0..0..1..0..0..1..1....0..0..1..0..1..1..0
..3..0..0..2..1..3..2....2..1..0..1..3..1..3....0..2..1..2..3..3..0
..0..1..1..2..0..1..2....3..1..1..3..0..2..0....3..2..2..0..1..2..3
..1..3..0..0..1..3..3....0..2..0..0..1..1..3....2..0..1..3..1..1..2
..2..0..2..2..1..1..0....3..0..3..1..1..3..2....0..2..1..3..3..1..2
		
Showing 1-8 of 8 results.