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.

A197244 Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,0,1,1,1 for x=0,1,2,3,4.

Original entry on oeis.org

2, 4, 8, 16, 40, 80, 192, 400, 936, 1984, 4576, 9824, 22408, 48560, 109888, 239728, 539432, 1182432, 2649952, 5828544, 13024648, 28717648, 64040768, 141448528, 314965928, 696544000, 1549366240, 3429474848, 7622621832, 16883244016
Offset: 1

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Author

R. H. Hardin, Oct 12 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's.
Column 2 of A197250.

Examples

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

Crossrefs

Cf. A197250.

Formula

Empirical: a(n) = 4*a(n-2) +2*a(n-3) +a(n-4) -2*a(n-5).
Empirical g.f.: 2*x*(1 - x)*(1 + x)^3 / (1 - 4*x^2 - 2*x^3 - x^4 + 2*x^5). - Colin Barker, May 11 2018

A197245 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,0,1,1,1 for x=0,1,2,3,4.

Original entry on oeis.org

1, 8, 3, 53, 110, 227, 1035, 2004, 7529, 20633, 53902, 172997, 474139, 1395792, 4009631, 11336881, 33563326, 95906965, 275694011, 796470870, 2294495057, 6647188965, 19110664400, 55033208033, 159018294491, 458707454692
Offset: 1

Views

Author

R. H. Hardin Oct 12 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
Column 3 of A197250

Examples

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

Formula

Empirical: a(n) = a(n-2) +9*a(n-3) +26*a(n-4) +58*a(n-5) -25*a(n-6) -148*a(n-7) -104*a(n-8) -114*a(n-9) +55*a(n-10) -149*a(n-11) +186*a(n-12) -9*a(n-13) +39*a(n-14) -55*a(n-15) +21*a(n-16) +a(n-17) +2*a(n-18) -a(n-19) for n>20

A197246 Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,0,1,1,1 for x=0,1,2,3,4.

Original entry on oeis.org

1, 16, 53, 275, 780, 5713, 16773, 98870, 393913, 1869033, 8527840, 32730687, 177791439, 674100600, 3386483171, 13856198755, 66236228308, 289604893615, 1242844626331, 5912414575588, 24990706118619, 116867053171491
Offset: 1

Views

Author

R. H. Hardin Oct 12 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
Column 4 of A197250

Examples

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

Formula

Empirical: a(n) = 5*a(n-2) +12*a(n-3) +134*a(n-4) +160*a(n-5) -615*a(n-6) +12174*a(n-7) -518*a(n-8) -47245*a(n-9) -44364*a(n-10) +38534*a(n-11) +120522*a(n-12) -170702*a(n-13) -87919*a(n-14) -4472*a(n-15) +682511*a(n-16) -390368*a(n-17) +333704*a(n-18) -949248*a(n-19) +1346705*a(n-20) -1109007*a(n-21) +1033190*a(n-22) -2853866*a(n-23) +1697513*a(n-24) +872394*a(n-25) +1858574*a(n-26) +533223*a(n-27) -3166721*a(n-28) +1038785*a(n-29) -2246717*a(n-30) +2216266*a(n-31) -1520506*a(n-32) +1327738*a(n-33) -734503*a(n-34) +531200*a(n-35) -302942*a(n-36) +85056*a(n-37) -52786*a(n-38) +18048*a(n-39) +9507*a(n-40) -770*a(n-41) +911*a(n-42) -852*a(n-43) +25*a(n-44) +25*a(n-45) -180*a(n-46) -55*a(n-47) +15*a(n-48) +10*a(n-49) for n>50

A197247 Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,0,1,1,1 for x=0,1,2,3,4.

Original entry on oeis.org

3, 40, 110, 780, 5062, 31276, 213912, 1244680, 8149652, 54813300, 363207297, 2334210952, 15099425049, 99496688244, 657733281792, 4291822021778, 27959094118746, 183056501656614, 1201021999376817, 7872982494463940
Offset: 1

Views

Author

R. H. Hardin Oct 12 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
Column 5 of A197250

Examples

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

A197248 Number of nX6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,0,1,1,1 for x=0,1,2,3,4.

Original entry on oeis.org

3, 80, 227, 5713, 31276, 405065, 3264225, 29975706, 324191969, 2687575073, 30493965518, 259733680667, 2634174755809, 25422825883256, 236887111563899, 2418154978600875, 22091513472216108, 220206294709791833
Offset: 1

Views

Author

R. H. Hardin Oct 12 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
Column 6 of A197250

Examples

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

A197249 Number of nX7 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,0,1,1,1 for x=0,1,2,3,4.

Original entry on oeis.org

2, 192, 1035, 16773, 213912, 3264225, 48703999, 692974749, 9613268927, 144634486646, 2038308764828, 29317910548935, 416838295672468, 6110472912181664, 87970427980764925, 1247341042216025997
Offset: 1

Views

Author

R. H. Hardin Oct 12 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
Column 7 of A197250

Examples

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

A197243 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 0,0,1,1,1 for x=0,1,2,3,4.

Original entry on oeis.org

1, 4, 3, 275, 5062, 405065, 48703999, 11304892092, 9455531359836, 13086658688226332
Offset: 1

Views

Author

R. H. Hardin Oct 12 2011

Keywords

Comments

Every 0 is next to 0 0's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 1's, every 4 is next to 4 1's
Diagonal of A197250

Examples

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