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 1-8 of 8 results.

A208001 T(n,k)=Number of n X k nonnegative integer arrays with new values 0 upwards introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).

Original entry on oeis.org

1, 2, 2, 5, 15, 5, 15, 114, 114, 15, 52, 1657, 4141, 1657, 52, 203, 36401, 426422, 426422, 36401, 203, 877, 1094076, 86545486, 450288795, 86545486, 1094076, 877, 4140, 42436913, 29169661126, 1182700979380, 1182700979380, 29169661126, 42436913, 4140
Offset: 1

Views

Author

R. H. Hardin, Feb 22 2012

Keywords

Examples

			Table starts
....1........2...........5............15............52.........203
....2.......15.........114..........1657.........36401.....1094076
....5......114........4141........426422......86545486.29169661126
...15.....1657......426422.....450288795.1182700979380
...52....36401....86545486.1182700979380
..203..1094076.29169661126
..877.42436913
.4140
...
Some solutions for n=4 k=3
..0..0..0....0..0..0....0..0..0....0..1..0....0..0..1....0..0..0....0..0..0
..1..0..1....1..2..1....1..0..1....1..0..1....0..0..1....1..0..1....1..0..1
..2..1..2....2..1..2....2..1..2....0..1..2....2..2..1....2..1..2....2..2..2
..1..0..3....3..0..0....1..0..1....1..2..1....2..3..1....1..2..1....1..0..1
		

Crossrefs

Columns 1..4 are A000110, A207998, A207999, A208000.
Main diagonal is A361453.
Cf. A208434 (3 colorings), A208353 (4 colorings).
Cf. A207868 (grid graph).

A208347 Number of nX2 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).

Original entry on oeis.org

2, 15, 100, 868, 7780, 69988, 629860, 5668708, 51018340, 459165028, 4132485220, 37192366948, 334731302500, 3012581722468, 27113235502180, 244019119519588, 2196172075676260, 19765548681086308, 177889938129776740
Offset: 1

Views

Author

R. H. Hardin Feb 25 2012

Keywords

Comments

Column 2 of A208353

Examples

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

Formula

Empirical: a(n) = 10*a(n-1) -9*a(n-2) for n>4

A208348 Number of nX3 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).

Original entry on oeis.org

5, 100, 1095, 12625, 153237, 1901508, 23658861, 294608660, 3672171940, 45806539501, 571496743787, 7130666296577, 88976864630029, 1110304369879641, 13855224093424061, 172897096309149243, 2157565319312754303
Offset: 1

Views

Author

R. H. Hardin Feb 25 2012

Keywords

Comments

Column 3 of A208353

Examples

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

Formula

Empirical: a(n) = 21*a(n-1) -90*a(n-2) -532*a(n-3) +5973*a(n-4) -31315*a(n-5) +73172*a(n-6) +692866*a(n-7) -5872588*a(n-8) +14338130*a(n-9) +13545534*a(n-10) -238643374*a(n-11) +1047870400*a(n-12) -1941550084*a(n-13) -2024947104*a(n-14) +17313536656*a(n-15) -33786142200*a(n-16) +21548688152*a(n-17) +32421829160*a(n-18) -107335908376*a(n-19) +165792590624*a(n-20) -118619608528*a(n-21) -73538891712*a(n-22) +207386497216*a(n-23) -223952516832*a(n-24) +322902169696*a(n-25) -245567709568*a(n-26) -217360125376*a(n-27) +464272398720*a(n-28) -172433924352*a(n-29) -145159584768*a(n-30) +86842756096*a(n-31) +128366311424*a(n-32) -108640727040*a(n-33) -53571584000*a(n-34) +74317824000*a(n-35) -18063360000*a(n-36) for n>39

A208349 Number of n X 4 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).

Original entry on oeis.org

15, 868, 12625, 230387, 4773885, 103672036, 2280287753, 50481169071, 1122098238432, 24983185355723, 556622494082921, 12405478452873059, 276529980588607690, 6164555722628477878, 137428302821781111484
Offset: 1

Views

Author

R. H. Hardin Feb 25 2012

Keywords

Comments

Column 4 of A208353.

Examples

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

Crossrefs

Cf. A208353.

A208350 Number of nX5 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).

Original entry on oeis.org

51, 7780, 153237, 4773885, 191586797, 8045978096, 340596199800, 14513602070899, 621231491393354, 26619820042892506, 1141266433540198765, 48945495491297801080, 2099487944721769270814, 90063058254133100176716
Offset: 1

Views

Author

R. H. Hardin Feb 25 2012

Keywords

Comments

Column 5 of A208353

Examples

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

A208346 Number of n X n 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).

Original entry on oeis.org

1, 15, 1095, 230387, 191586797, 647640659639
Offset: 1

Views

Author

R. H. Hardin Feb 25 2012

Keywords

Comments

Diagonal of A208353

Examples

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

A208351 Number of nX6 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).

Original entry on oeis.org

187, 69988, 1901508, 103672036, 8045978096, 647640659639, 52428246114853
Offset: 1

Views

Author

R. H. Hardin Feb 25 2012

Keywords

Comments

Column 6 of A208353

Examples

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

A208352 Number of nX7 0..3 arrays with new values 0..3 introduced in row major order and no element equal to any knight-move neighbor (colorings ignoring permutations of colors).

Original entry on oeis.org

715, 629860, 23658861, 2280287753, 340596199800, 52428246114853
Offset: 1

Views

Author

R. H. Hardin Feb 25 2012

Keywords

Comments

Column 7 of A208353

Examples

			Some solutions for n=4
..0..0..0..1..2..0..3....0..0..0..0..0..0..0....0..0..0..1..0..1..2
..3..2..3..1..1..0..1....1..1..1..2..1..1..1....3..2..1..3..3..2..3
..1..3..2..3..2..0..2....2..1..2..2..3..3..2....2..1..2..3..2..1..0
..0..1..3..2..3..2..3....3..3..0..0..3..3..2....0..2..0..2..1..0..0
		
Showing 1-8 of 8 results.