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.

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A200801 T(n,k) is the number of n X k 0..3 arrays with values 0..3 introduced in row major order and each element equal to no more than two horizontal and vertical neighbors.

Original entry on oeis.org

1, 2, 2, 5, 15, 5, 15, 178, 178, 15, 51, 2614, 9880, 2614, 51, 187, 40148, 583813, 583813, 40148, 187, 715, 622645, 34679839, 132636590, 34679839, 622645, 715, 2795, 9676364, 2060918000, 30147154218, 30147154218, 2060918000, 9676364, 2795
Offset: 1

Views

Author

R. H. Hardin, Nov 22 2011

Keywords

Examples

			Table starts:
.....1...........2.................5......................15
.....2..........15...............178....................2614
.....5.........178..............9880..................583813
....15........2614............583813...............132636590
....51.......40148..........34679839.............30147154218
...187......622645........2060918000...........6852264918471
...715.....9676364......122478253815........1557479347400065
..2795...150442627.....7278777317468......354005859128023982
.11051..2339207390...432571571252989....80463441477635545163
.43947.36372631268.25707362563355693.18288865135614195620421
...
Some solutions for n=5 and k=3:
..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..1..0....0..1..0....0..1..0....0..1..0....0..1..0....0..1..0....0..1..0
..2..0..0....0..1..1....0..0..2....2..2..0....2..2..0....2..2..0....2..1..2
..2..3..3....1..0..2....3..1..0....1..1..1....3..2..2....0..0..1....0..1..3
..2..2..0....3..2..1....3..3..0....2..2..1....3..1..3....1..1..1....1..1..2
		

Crossrefs

Main diagonal is A200794.
Columns 1..7 are A007581(n-1), A200795, A200796, A200797, A200798, A200799, A200780.

A241119 T(n,k)=Number of nXk 0..3 arrays with no element equal to exactly three horizontal or vertical neighbors, with new values 0..3 introduced in row major order.

Original entry on oeis.org

1, 2, 2, 5, 15, 5, 15, 178, 178, 15, 51, 2614, 9918, 2614, 51, 187, 40148, 587555, 587555, 40148, 187, 715, 622645, 35000157, 134229632, 35000157, 622645, 715, 2795, 9676364, 2085879115, 30679522712, 30679522712, 2085879115, 9676364, 2795
Offset: 1

Views

Author

R. H. Hardin, Apr 16 2014

Keywords

Comments

Table starts
...1......2..........5............15................51..................187
...2.....15........178..........2614.............40148...............622645
...5....178.......9918........587555..........35000157...........2085879115
..15...2614.....587555.....134229632.......30679522712........7012241396116
..51..40148...35000157...30679522712....26891788727245....23571710809729613
.187.622645.2085879115.7012241396116.23571710809729613.79236581561126536192

Examples

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

Crossrefs

Column 1 is A007581(n-1)
Column 2 is A200795

Formula

Empirical for column k:
k=1: a(n) = 7*a(n-1) -14*a(n-2) +8*a(n-3)
k=2: [order 8] for n>10
k=3: [order 20] for n>21
k=4: [order 74] for n>75
Showing 1-2 of 2 results.