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.

A197444 Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

2, 5, 12, 36, 107, 321, 957, 2868, 8581, 25694, 76914, 230273, 689377, 2063867, 6178778, 18498023, 55379290, 165794354, 496354537, 1485984549, 4448735449, 13318609060, 39873206463, 119372269782, 357376295102, 1069911935955
Offset: 1

Views

Author

R. H. Hardin, Oct 15 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's.
Column 2 of A197450.

Examples

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

Crossrefs

Cf. A197450.

Formula

Empirical: a(n) = 2*a(n-1) +5*a(n-2) -4*a(n-3) -6*a(n-4) -a(n-5) +4*a(n-7) +a(n-8).
Empirical g.f.: x*(2 + x - 8*x^2 - 5*x^3 + 7*x^4 + 7*x^5 + x^6 - 3*x^7) / ((1 - x)*(1 - x - 6*x^2 - 2*x^3 + 4*x^4 + 5*x^5 + 5*x^6 + x^7)). - Colin Barker, May 12 2018

A197445 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

3, 12, 81, 474, 2678, 15410, 88767, 510482, 2936714, 16895217, 97197637, 559175541, 3216923150, 18506887013, 106469709385, 612517802024, 3523801014059, 20272347435052, 116626354899557, 670948774602366, 3859953085161367
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 3 of A197450

Examples

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

Formula

Empirical: a(n) = 2*a(n-1) +12*a(n-2) +45*a(n-3) +61*a(n-4) +20*a(n-5) -129*a(n-6) -324*a(n-7) -344*a(n-8) -166*a(n-9) +61*a(n-10) +268*a(n-11) +360*a(n-12) +307*a(n-13) +240*a(n-14) +92*a(n-15) -97*a(n-16) -142*a(n-17) -120*a(n-18) -92*a(n-19) -32*a(n-20) -4*a(n-22) for n>25

A197446 Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

4, 36, 474, 4837, 52117, 585194, 6455759, 71202438, 787298158, 8700460833, 96129107870, 1062244177133, 11737953179188, 129703872646573, 1433228960340464, 15837211757913841, 175001375414696401
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 4 of A197450

Examples

			Some solutions containing all values 0 to 4 for n=5
..0..1..1..2....0..0..1..1....0..3..0..0....0..0..0..0....0..0..0..0
..3..0..0..1....0..4..0..0....3..0..4..0....3..0..4..0....0..4..0..0
..0..0..0..1....3..0..3..0....0..0..0..1....0..0..0..1....0..0..3..0
..0..4..0..0....0..1..2..1....0..3..0..1....0..3..0..1....0..1..2..1
..0..0..3..0....0..1..2..1....0..1..1..2....0..1..1..2....0..1..2..1
		

Formula

Empirical: a(n) = 5*a(n-1) +43*a(n-2) +266*a(n-3) +239*a(n-4) -1960*a(n-5) -10352*a(n-6) -9192*a(n-7) +37799*a(n-8) +105029*a(n-9) -18744*a(n-10) -238355*a(n-11) -126539*a(n-12) +355537*a(n-13) +283213*a(n-14) -719109*a(n-15) -385554*a(n-16) +828862*a(n-17) +1313412*a(n-18) -2023532*a(n-19) -2243258*a(n-20) +1255883*a(n-21) +1718260*a(n-22) -1386751*a(n-23) -2333466*a(n-24) +1949938*a(n-25) +3566040*a(n-26) -4067978*a(n-27) -123658*a(n-28) +2185717*a(n-29) +1568417*a(n-30) -1624352*a(n-31) -2532073*a(n-32) +4246890*a(n-33) -1297116*a(n-34) -1336520*a(n-35) +1883451*a(n-36) -1106741*a(n-37) +813615*a(n-38) -847011*a(n-39) -13406*a(n-40) +890240*a(n-41) -936883*a(n-42) +427611*a(n-43) +113100*a(n-44) -369138*a(n-45) +191138*a(n-46) +24776*a(n-47) -53551*a(n-48) +9522*a(n-49) +1877*a(n-50) +85*a(n-51) -54*a(n-52) +36*a(n-53) for n>56

A197447 Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

7, 107, 2678, 52117, 1108699, 23829080, 504568165, 10724642167, 228248265080, 4853181015432, 103200753393047, 2194748772730124, 46673287485335449, 992547357156970890, 21107504726738892508, 448871249985110511395
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 5 of A197450

Examples

			Some solutions containing all values 0 to 4 for n=4
..0..3..0..3..0....0..3..0..3..0....0..0..0..0..0....0..0..0..3..0
..1..0..0..0..0....1..0..4..0..3....1..0..4..0..0....0..0..4..0..1
..1..0..0..4..0....1..0..0..4..0....1..0..0..0..3....0..0..0..0..1
..2..1..1..0..0....2..1..1..0..0....2..1..1..0..0....0..0..1..1..2
		

A197448 Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

11, 321, 15410, 585194, 23829080, 982926107, 40087361395, 1640477445822, 67160665746869, 2747685400705119, 112433629005651948, 4600917175526994358, 188267595598497672073, 7703877269427034462338, 315242428170240015474340
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 6 of A197450

Examples

			Some solutions containing all values 0 to 4 for n=4
..1..1..0..0..3..0....2..1..1..0..1..1....0..0..0..1..2..1....0..0..0..0..1..1
..2..2..3..0..0..3....1..0..0..0..0..0....0..0..0..1..2..1....1..3..0..4..0..0
..1..1..0..0..4..0....1..0..4..0..0..0....0..0..4..0..3..0....1..0..0..0..0..3
..0..0..3..0..0..0....0..3..0..0..3..0....0..0..0..3..0..0....2..1..1..0..0..0
		

A197449 Number of nX7 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

16, 957, 88767, 6455759, 504568165, 40087361395, 3148323076125, 247785141871837, 19514460176530843, 1536223846055481075, 120945067934443941208, 9522042330180130196817, 749659600975504964938552
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 7 of A197450

Examples

			Some solutions containing all values 0 to 4 for n=4
..0..0..3..0..0..3..0....0..0..3..0..0..0..0....0..0..0..0..1..1..0
..0..3..0..0..4..0..1....1..0..0..4..0..3..1....1..3..0..4..0..0..1
..0..3..0..0..0..0..1....1..0..3..0..0..0..1....1..0..0..0..3..0..1
..0..0..3..0..1..1..2....2..1..1..0..3..0..0....0..0..3..0..1..1..2
		

A197443 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,1,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

1, 5, 81, 4837, 1108699, 982926107, 3148323076125, 37516007592943532, 1657994465210882573048
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Diagonal of A197450

Examples

			Some solutions containing all values 0 to 4 for n=4
..0..3..0..0....2..1..1..0....0..1..1..2....0..0..3..0....2..1..1..0
..1..0..4..0....1..0..0..3....0..0..0..1....0..4..0..1....1..0..0..3
..1..0..0..3....1..0..4..0....0..4..0..1....0..0..0..1....1..0..4..0
..2..1..1..0....0..0..0..0....0..0..3..0....0..1..1..2....0..3..0..0
		
Showing 1-7 of 7 results.