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.

A232155 Number of n X 2 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, vertically or antidiagonally, and no adjacent values equal.

Original entry on oeis.org

2, 18, 62, 218, 746, 2600, 9004, 31262, 108492, 376566, 1307146, 4537292, 15750222, 54673186, 189786782, 658806476, 2286917482, 7938591212, 27557292770, 95659868830, 332064969492, 1152700237642, 4001379292082, 13890026339060
Offset: 1

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Author

R. H. Hardin, Nov 19 2013

Keywords

Examples

			Some solutions for n=7:
..2..1....2..3....3..1....0..3....1..3....0..1....0..1....2..1....3..0....1..2
..3..0....0..1....0..2....1..2....2..1....2..3....3..2....3..2....1..3....0..3
..2..3....2..3....3..1....3..0....3..0....1..2....0..1....1..0....2..0....1..0
..1..2....0..1....2..0....2..1....1..2....0..3....3..2....3..2....1..3....2..1
..3..1....2..3....3..1....3..2....3..1....1..0....1..3....0..1....2..1....3..0
..2..0....1..2....0..2....1..0....2..3....2..3....2..1....3..2....3..0....1..2
..3..2....0..3....1..3....2..3....1..0....1..2....3..2....0..1....2..1....3..1
		

Crossrefs

Column 2 of A232161.

Formula

Empirical: a(n) = 4*a(n-1) + 2*a(n-2) - 13*a(n-3) - 5*a(n-4) + 14*a(n-5) - 3*a(n-6) + 3*a(n-7) + 8*a(n-8) + a(n-9) - a(n-10) for n>11.
Empirical g.f.: 2*x*(1 + 5*x - 7*x^2 - 20*x^3 - 3*x^4 + 24*x^5 + 5*x^6 + 7*x^7 + 15*x^8 + 2*x^9 - 2*x^10) / (1 - 4*x - 2*x^2 + 13*x^3 + 5*x^4 - 14*x^5 + 3*x^6 - 3*x^7 - 8*x^8 - x^9 + x^10). - Colin Barker, Oct 03 2018

A232156 Number of nX3 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, vertically or antidiagonally, and no adjacent values equal.

Original entry on oeis.org

4, 62, 290, 1284, 5902, 27086, 124436, 572080, 2629946, 12090710, 55591878, 255589946, 1175154022, 5403111082, 24842308392, 114220099740, 525160514282, 2414582116408, 11101765510580, 51043677955498, 234688597761528
Offset: 1

Views

Author

R. H. Hardin, Nov 19 2013

Keywords

Comments

Column 3 of A232161

Examples

			Some solutions for n=7
..1..2..3....1..2..3....0..1..2....1..2..3....2..1..0....0..3..1....2..1..2
..3..1..0....3..1..2....2..0..3....3..0..1....3..2..1....1..2..0....3..0..3
..0..3..2....2..0..3....3..2..1....1..2..0....1..0..2....0..3..2....1..2..1
..2..0..1....3..1..2....1..0..3....0..3..2....2..3..0....2..0..3....3..0..2
..1..3..0....2..3..0....3..2..1....2..0..3....1..2..1....1..2..0....2..3..0
..0..2..1....1..2..1....0..3..0....3..1..2....0..3..0....3..1..3....0..1..2
..3..0..3....0..3..0....1..2..1....0..3..1....2..1..3....2..0..2....2..3..1
		

Formula

Empirical: a(n) = 8*a(n-1) -12*a(n-2) -33*a(n-3) +40*a(n-4) +286*a(n-5) -545*a(n-6) -642*a(n-7) +2651*a(n-8) -1783*a(n-9) -2378*a(n-10) +4407*a(n-11) -1301*a(n-12) -2857*a(n-13) +3373*a(n-14) +157*a(n-15) -2558*a(n-16) +366*a(n-17) +1084*a(n-18) +818*a(n-19) -2988*a(n-20) -2028*a(n-21) +2529*a(n-22) +1294*a(n-23) +328*a(n-24) +582*a(n-25) -122*a(n-26) -180*a(n-27) +47*a(n-28) +21*a(n-29) -3*a(n-30) for n>33

A232157 Number of nX4 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, vertically or antidiagonally, and no adjacent values equal.

Original entry on oeis.org

8, 218, 1284, 7770, 46702, 286770, 1767266, 10830650, 66701686, 410364610, 2522566124, 15524673872, 95489164864, 587352257166, 3613537440642, 22227593479382, 136734516680534, 841147631122416, 5174280907720634
Offset: 1

Views

Author

R. H. Hardin, Nov 19 2013

Keywords

Comments

Column 4 of A232161

Examples

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

Formula

Empirical recurrence of order 94 (see link above)

A232158 Number of nX5 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, vertically or antidiagonally, and no adjacent values equal.

Original entry on oeis.org

14, 746, 5902, 46702, 382996, 3183932, 26694774, 223026806, 1869037596, 15673051556, 131274639250, 1100535460668, 9225695626046, 77312726353080, 648103682234572, 5432428499191068, 45531948090605296, 381665246488467802
Offset: 1

Views

Author

R. H. Hardin, Nov 19 2013

Keywords

Comments

Column 5 of A232161

Examples

			Some solutions for n=4
..0..1..0..2..0....0..3..1..0..3....1..0..3..1..3....2..0..2..3..2
..3..2..3..1..3....1..0..2..1..0....2..1..2..0..2....3..1..0..1..3
..0..1..2..0..1....2..3..0..2..3....3..0..3..1..0....0..2..3..2..1
..2..3..1..3..2....1..2..3..1..0....2..1..2..3..2....3..0..1..3..2
		

A232159 Number of nX6 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, vertically or antidiagonally, and no adjacent values equal.

Original entry on oeis.org

26, 2600, 27086, 286770, 3183932, 36275078, 415332300, 4764939084, 54785401618, 629979277720, 7246595856072, 83366908500616, 959177256873984, 11035264357800498, 126966562329855518, 1460839965204197890
Offset: 1

Views

Author

R. H. Hardin, Nov 19 2013

Keywords

Comments

Column 6 of A232161

Examples

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

A232160 Number of nX7 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, vertically or antidiagonally, and no adjacent values equal.

Original entry on oeis.org

48, 9004, 124436, 1767266, 26694774, 415332300, 6564512068, 103384156384, 1636124088162, 25973583237174, 411171410014356, 6519608941018384, 103473233282931542, 1639791299611784558, 26009017324816484476
Offset: 1

Views

Author

R. H. Hardin, Nov 19 2013

Keywords

Comments

Column 7 of A232161

Examples

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

A232154 Number of n X n 0..3 arrays with every 0 next to a 1, every 1 next to a 2 and every 2 next to a 3 horizontally, vertically or antidiagonally, and no adjacent values equal.

Original entry on oeis.org

1, 18, 290, 7770, 382996, 36275078, 6564512068, 2246994465516, 1482101422338982, 1881388287368571956
Offset: 1

Views

Author

R. H. Hardin, Nov 19 2013

Keywords

Comments

Diagonal of A232161

Examples

			Some solutions for n=4
..3..2..0..3....0..1..3..2....2..1..3..2....1..2..3..2....3..0..2..1
..0..1..2..1....3..2..0..1....3..0..1..0....0..1..0..3....1..3..0..3
..3..0..3..2....1..3..2..3....1..3..2..1....2..3..2..1....2..1..2..1
..1..2..0..1....2..1..0..2....2..1..3..0....0..1..0..3....3..0..3..2
		
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