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.

A197469 Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,1,0,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

1, 2, 6, 12, 24, 50, 98, 194, 394, 786, 1562, 3138, 6282, 12530, 25082, 50210, 100330, 200658, 401498, 802818, 1605450, 3211442, 6422714, 12844514, 25690282, 51381138, 102759194, 205520322, 411044874, 822081650, 1644162938, 3288342434
Offset: 1

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Author

R. H. Hardin, Oct 15 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's.
Column 2 of A197475.

Examples

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

Crossrefs

Cf. A197475.

Formula

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

A197470 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,1,0,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

3, 6, 26, 46, 181, 374, 1300, 2886, 9446, 22060, 69096, 167466, 507600, 1265434, 3741192, 9529514, 27644128, 71580304, 204668940, 536641128, 1517618972, 4017418484, 11266355518, 30042504088, 83713614532, 224474050480
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 3 of A197475

Examples

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

Formula

Empirical: a(n) = 6*a(n-2) +3*a(n-3) +4*a(n-4) -2*a(n-5) +2*a(n-6) -7*a(n-7) -19*a(n-8) -23*a(n-9) -19*a(n-10) -19*a(n-11) -4*a(n-12) -4*a(n-13) for n>16

A197471 Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,1,0,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

1, 12, 46, 184, 748, 2824, 10934, 42474, 164782, 638460, 2473902, 9589038, 37167908, 144059050, 558354234, 2164121964, 8387927204, 32510787510, 126008566828, 488396574430, 1892976376006, 7336987712088, 28437432700816, 110220652223106
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 4 of A197475

Examples

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

Formula

Empirical: a(n) = a(n-1) +5*a(n-2) +19*a(n-3) +15*a(n-4) +24*a(n-5) -17*a(n-6) -55*a(n-7) -114*a(n-8) +5*a(n-9) +182*a(n-10) +372*a(n-11) +28*a(n-12) -230*a(n-13) -289*a(n-14) -284*a(n-15) -44*a(n-16) +101*a(n-17) +174*a(n-18) -28*a(n-19) +80*a(n-20) +8*a(n-21) -8*a(n-22) +144*a(n-23) -48*a(n-25) for n>28

A197472 Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,1,0,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

4, 24, 181, 748, 5408, 22672, 151748, 684002, 4368923, 20344854, 126020110, 603916958, 3643523708, 17866994674, 105586791488, 527450827498, 3064686007756, 15542757419162, 89084044386061, 457335065118848
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 5 of A197475

Examples

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

Formula

Empirical: a(n) = 15*a(n-2) +52*a(n-3) +296*a(n-4) -554*a(n-5) -229*a(n-6) -6613*a(n-7) -4335*a(n-8) -20874*a(n-9) +18040*a(n-10) +26381*a(n-11) +197933*a(n-12) +94070*a(n-13) +320192*a(n-14) -611325*a(n-15) -1087899*a(n-16) -3359414*a(n-17) -3589742*a(n-18) -3585120*a(n-19) +1625011*a(n-20) +12448300*a(n-21) +40979440*a(n-22) +72913510*a(n-23) +84642420*a(n-24) +58563471*a(n-25) -78408358*a(n-26) -285525148*a(n-27) -449083891*a(n-28) -430038062*a(n-29) -48315877*a(n-30) +332137526*a(n-31) +647232602*a(n-32) +895796784*a(n-33) +402347451*a(n-34) -71569578*a(n-35) -971116816*a(n-36) -915055737*a(n-37) -564795248*a(n-38) -408261834*a(n-39) +1616488905*a(n-40) +1209618295*a(n-41) +359637734*a(n-42) +1627078813*a(n-43) +458140995*a(n-44) -1790490027*a(n-45) -302830462*a(n-46) +118180618*a(n-47) -2049684292*a(n-48) -430429020*a(n-49) +1970991956*a(n-50) -371957378*a(n-51) -1143603688*a(n-52) +1515158904*a(n-53) +487108128*a(n-54) -935714152*a(n-55) +420116328*a(n-56) +641573360*a(n-57) -440594128*a(n-58) -327892352*a(n-59) +177462144*a(n-60) +7058112*a(n-61) -111894784*a(n-62) +26606336*a(n-63) +48291584*a(n-64) -3591168*a(n-65) -8124416*a(n-66) +135168*a(n-67) +61440*a(n-68) for n>71

A197473 Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,1,0,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

4, 50, 374, 2824, 22672, 165200, 1265828, 9507212, 72145488, 544829612, 4121917612, 31166838320, 235726500646, 1782712177744, 13482608699280, 101968288116918, 771180418816752, 5832406885650952, 44110365514811080
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 6 of A197475

Examples

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

A197474 Number of nX7 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,1,0,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

5, 98, 1300, 10934, 151748, 1265828, 16544206, 145244408, 1830370547, 16537658774, 202870487557, 1878224690406, 22527034080238, 212875475502774, 2505004507267645, 24087191716817350, 278905922435987885
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 7 of A197475

Examples

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

A197468 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 0,1,0,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

1, 2, 26, 184, 5408, 165200, 16544206, 2117012786, 779857304215, 396015611721478, 546971557228648382
Offset: 1

Views

Author

R. H. Hardin Oct 15 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 1's, every 2 is next to 2 0's, every 3 is next to 3 0's, every 4 is next to 4 0's
Diagonal of A197475

Examples

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