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 1-10 of 13 results. Next

A269269 Number of n X n 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

0, 108, 46872, 74853576, 542973139128, 19356924219624936, 3516906597130333936872, 3322606082327701612506093240, 16524782213263820847479975782463640
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Comments

Diagonal of A269276.

Examples

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

Crossrefs

Cf. A269276.

A269270 Number of n X 2 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

4, 108, 1620, 20412, 236196, 2598156, 27634932, 286978140, 2927177028, 29443957164, 292889889684, 2887057484028, 28242953648100, 274521509459532, 2653707924775476, 25530500379736476, 244598664928443012
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Examples

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

Crossrefs

Column 2 of A269276.

Formula

Empirical: a(n) = 18*a(n-1) - 81*a(n-2).
Conjectures from Colin Barker, Jan 20 2019: (Start)
G.f.: 4*x*(1 + 9*x) / (1 - 9*x)^2.
a(n) = 9^(n-1) * (8*n-4).
(End)

A269271 Number of n X 3 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

24, 1368, 46872, 1365336, 36673560, 938176344, 23230366488, 561939624792, 13356872620056, 313173275509080, 7262896745936664, 166932248829835608, 3808216985895026712, 86327991673633618776, 1946351959512905208600
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Examples

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

Crossrefs

Column 3 of A269276.

Formula

Empirical: a(n) = 42*a(n-1) - 441*a(n-2).
Conjectures from Colin Barker, Jan 20 2019: (Start)
G.f.: 24*x*(1 + 15*x) / (1 - 21*x)^2.
a(n) = 8*3^n * 7^(n-2) * (12*n-5).
(End)

A269272 Number of n X 4 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

108, 13896, 1104264, 74853576, 4684312584, 279339197256, 16128206816904, 909870855444936, 50443519266217224, 2758864964165996616, 149253876730080113544, 8002845140585293252296, 425920265748436386105864
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Examples

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

Crossrefs

Column 4 of A269276.

Formula

Empirical: a(n) = 98*a(n-1) - 2401*a(n-2) for n > 3.
Conjectures from Colin Barker, Jan 20 2019: (Start)
G.f.: 36*x*(3 + 92*x + 49*x^2) / (1 - 49*x)^2.
a(n) = 72 * 49^(n-2) * (120*n-47) for n>1.
(End)

A269273 Number of n X 5 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

432, 127512, 23549400, 3719884392, 542973139128, 75556007986536, 10181956012212600, 1340897428986116904, 173553231095580128184, 22161410569440812760552, 2799318884872209986120184
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Examples

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

Crossrefs

Column 5 of A269276.

Formula

Empirical: a(n) = 234*a(n-1) - 14277*a(n-2) + 68796*a(n-3) - 86436*a(n-4).
Empirical g.f.: 72*x*(6 + 367*x - 1677*x^2 + 1302*x^3) / (1 - 117*x + 294*x^2)^2. - Colin Barker, Jan 21 2019

A269274 Number of nX6 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

1620, 1104264, 474819408, 174924572760, 59587625651904, 19356924219624936, 6090616046325570480, 1872977567099580289656, 566116324214731470647712, 168820920854627863029497352, 49802534018235803452666079376
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Comments

Column 6 of A269276.

Examples

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

Crossrefs

Cf. A269276.

Formula

Empirical: a(n) = 564*a(n-1) -87462*a(n-2) +2257724*a(n-3) -21169617*a(n-4) +76236552*a(n-5) -92236816*a(n-6) for n>7

A269275 Number of nX7 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

5832, 9211608, 9230973192, 7934992835112, 6310088238337128, 4786284820998999528, 3516906597130333936872, 2525822328725627338344168, 1783069155917082001205203176, 1241926797984458949166277812968
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Comments

Column 7 of A269276.

Examples

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

Crossrefs

Cf. A269276.

Formula

Empirical: a(n) = 1384*a(n-1) -566002*a(n-2) +61993580*a(n-3) -3083170217*a(n-4) +82564587476*a(n-5) -1288497445564*a(n-6) +12048887832352*a(n-7) -66380108132464*a(n-8) +198314583195456*a(n-9) -247475435747904*a(n-10) for n>11

A269277 Number of 2 X n 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

0, 108, 1368, 13896, 127512, 1104264, 9211608, 74853576, 596581272, 4684312584, 36347893848, 279339197256, 2129701963032, 16128206816904, 121439499248088, 909870855444936, 6787656513072792, 50443519266217224, 373614100586474328
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Examples

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

Crossrefs

Row 2 of A269276.

Formula

Empirical: a(n) = 14*a(n-1) - 49*a(n-2) for n>4.
Conjectures from Colin Barker, Jan 21 2019: (Start)
G.f.: 36*x^2*(3 - x)*(1 - x) / (1 - 7*x)^2.
a(n) = 72 * 7^(n-4) * (60*n-47) for n>2.
(End)

A269278 Number of 3 X n 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

0, 1620, 46872, 1104264, 23549400, 474819408, 9230973192, 174918307032, 3252108138552, 59583135523968, 1078987217468328, 19354648265646120, 344454190256524824, 6089633274402902448, 107049250394211722184
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Examples

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

Crossrefs

Row 3 of A269276.

Formula

Empirical: a(n) = 36*a(n-1) - 378*a(n-2) + 972*a(n-3) - 729*a(n-4) for n>7.
Empirical g.f.: 36*x^2*(45 - 318*x + 812*x^2 - 1698*x^3 + 2061*x^4 - 756*x^5) / (1 - 18*x + 27*x^2)^2. - Colin Barker, Jan 21 2019

A269279 Number of 4Xn 0..3 arrays with some element plus some horizontally or antidiagonally adjacent neighbor totalling three exactly once.

Original entry on oeis.org

0, 20412, 1365336, 74853576, 3719884392, 174924572760, 7934992835112, 350946381867480, 15232155757251048, 651580499598523992, 27551808205246504872, 1154085846201751972824, 47965168186749101620584
Offset: 1

Views

Author

R. H. Hardin, Feb 21 2016

Keywords

Comments

Row 4 of A269276.

Examples

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

Crossrefs

Cf. A269276.

Formula

Empirical: a(n) = 96*a(n-1) -3108*a(n-2) +40720*a(n-3) -265326*a(n-4) +931200*a(n-5) -1766452*a(n-6) +1678992*a(n-7) -622521*a(n-8) for n>12
Showing 1-10 of 13 results. Next