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 1-6 of 6 results.

A318337 Number of n X n 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Original entry on oeis.org

1, 6, 20, 67, 393, 4133, 86487, 3590263, 285034170, 43174729552, 12383193287684, 6712873423988949, 6871475875643572553, 13272675681120501977922, 48367944991570243925176462, 332490278773637201581189154380
Offset: 1

Views

Author

R. H. Hardin, Aug 24 2018

Keywords

Comments

Diagonal of A318343.

Examples

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

Crossrefs

Cf. A318343.

A318338 Number of nX3 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Original entry on oeis.org

4, 10, 20, 36, 76, 160, 344, 748, 1624, 3544, 7724, 16856, 36776, 80252, 175128, 382168, 833996, 1819992, 3971720, 8667356, 18914520, 41276600, 90076716, 196571800, 428972904, 936135100, 2042900376, 4458162072, 9728917388
Offset: 1

Views

Author

R. H. Hardin, Aug 24 2018

Keywords

Comments

Column 3 of A318343.

Examples

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

Crossrefs

Cf. A318343.

Formula

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

A318339 Number of nX4 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Original entry on oeis.org

8, 20, 36, 67, 148, 343, 817, 1975, 4788, 11644, 28327, 68949, 167840, 408591, 994711, 2421617, 5895464, 14352589, 34941627, 85066013, 207094729, 504175889, 1227425339, 2988189330, 7274801283, 17710636103, 43116865936, 104968794797
Offset: 1

Views

Author

R. H. Hardin, Aug 24 2018

Keywords

Comments

Column 4 of A318343.

Examples

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

Crossrefs

Cf. A318343.

Formula

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

A318340 Number of nX5 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Original entry on oeis.org

16, 42, 76, 148, 393, 1115, 3321, 10111, 30943, 95244, 293401, 904986, 2792217, 8617223, 26597072, 82096253, 253412398, 782236683, 2414640760, 7453642765, 23008358869, 71023687464, 219240636280, 676766784339, 2089089700480
Offset: 1

Views

Author

R. H. Hardin, Aug 24 2018

Keywords

Comments

Column 5 of A318343.

Examples

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

Crossrefs

Cf. A318343.

Formula

Empirical: a(n) = 3*a(n-1) +5*a(n-2) -12*a(n-3) -17*a(n-4) +20*a(n-5) +31*a(n-6) -13*a(n-7) -33*a(n-8) +a(n-9) +20*a(n-10) +2*a(n-11) -4*a(n-12) -3*a(n-13) +a(n-15) for n>18

A318341 Number of nX6 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Original entry on oeis.org

32, 89, 160, 343, 1115, 4133, 16267, 66070, 270320, 1112195, 4584060, 18912384, 78063418, 322286580, 1330722690, 5494862763, 22690219542, 93697259411, 386917457753, 1597759628888, 6597895365718, 27245818039527, 112510877313046
Offset: 1

Views

Author

R. H. Hardin, Aug 24 2018

Keywords

Comments

Column 6 of A318343.

Examples

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

Crossrefs

Cf. A318343.

Formula

Empirical: a(n) = 4*a(n-1) +9*a(n-2) -28*a(n-3) -57*a(n-4) +78*a(n-5) +199*a(n-6) -73*a(n-7) -366*a(n-8) -89*a(n-9) +336*a(n-10) +298*a(n-11) -42*a(n-12) -362*a(n-13) -234*a(n-14) +215*a(n-15) +227*a(n-16) +16*a(n-17) -99*a(n-18) -65*a(n-19) +7*a(n-20) +27*a(n-21) +4*a(n-22) -4*a(n-23) for n>27

A318342 Number of nX7 0..1 arrays with every element unequal to 0, 1, 2 or 6 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.

Original entry on oeis.org

64, 190, 344, 817, 3321, 16267, 86487, 476348, 2647555, 14797928, 82863837, 464502820, 2605038853, 14613251568, 81984567828, 459986291171, 2580903334169, 14481247495703, 81253869292071, 455915278972371, 2558145839414926
Offset: 1

Views

Author

R. H. Hardin, Aug 24 2018

Keywords

Comments

Column 7 of A318343.

Examples

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

Crossrefs

Cf. A318343.

Formula

Empirical: a(n) = 6*a(n-1) +15*a(n-2) -89*a(n-3) -165*a(n-4) +555*a(n-5) +1215*a(n-6) -1671*a(n-7) -5290*a(n-8) +1469*a(n-9) +13428*a(n-10) +5625*a(n-11) -17967*a(n-12) -19967*a(n-13) +3366*a(n-14) +22938*a(n-15) +28588*a(n-16) +12646*a(n-17) -41780*a(n-18) -75067*a(n-19) +9433*a(n-20) +89071*a(n-21) +52784*a(n-22) -43392*a(n-23) -74658*a(n-24) -40*a(n-25) +41248*a(n-26) +12244*a(n-27) -12324*a(n-28) -4868*a(n-29) +3028*a(n-30) +660*a(n-31) -1352*a(n-32) -152*a(n-33) +496*a(n-34) +32*a(n-35) -64*a(n-36) for n>41
Showing 1-6 of 6 results.