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.

A223249 Two-loop graph coloring a rectangular array: number of n X 2 0..4 arrays where 0..4 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

Original entry on oeis.org

12, 52, 236, 1076, 4908, 22388, 102124, 465844, 2124972, 9693172, 44215916, 201693236, 920034348, 4196785268, 19143857644, 87325717684, 398340873132, 1817052930292, 8288582905196, 37808808665396, 172466877516588
Offset: 1

Views

Author

R. H. Hardin, Mar 18 2013

Keywords

Comments

Column 2 of A223255.

Examples

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

Crossrefs

Cf. A223255.

Formula

Empirical: a(n) = 5*a(n-1) - 2*a(n-2).
Conjectures from Colin Barker, Mar 16 2018: (Start)
G.f.: 4*x*(3 - 2*x) / (1 - 5*x + 2*x^2).
a(n) = (2^(1-n)*((5-sqrt(17))^n*(-1+sqrt(17)) + (1+sqrt(17))*(5+sqrt(17))^n)) / sqrt(17).
(End)

A223248 Two-loop graph coloring a rectangular array: number of n X n 0..4 arrays where 0..4 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

Original entry on oeis.org

5, 52, 2172, 307144, 200258884, 465277782336, 5036570504598960, 194136255385117730696, 34835929955107905273340132, 22243413468977139564311499153224, 66105120187260568220771918409079162896
Offset: 1

Views

Author

R. H. Hardin Mar 18 2013

Keywords

Comments

Diagonal of A223255

Examples

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

A223250 Two-loop graph coloring a rectangular array: number of n X 3 0..4 arrays where 0..4 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

Original entry on oeis.org

32, 236, 2172, 17828, 166892, 1382228, 12894316, 107283636, 996653548, 8326150836, 77047324460, 646086687220, 5957011569772, 50127570610868, 460630428892844, 3888717399278196, 35622664419652844, 301636706357260340
Offset: 1

Views

Author

R. H. Hardin, Mar 18 2013

Keywords

Comments

Column 3 of A223255.

Examples

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

Formula

Empirical: a(n) = 2*a(n-1) +75*a(n-2) -126*a(n-3) -70*a(n-4) +48*a(n-5).
Empirical g.f.: -4*x*(78*x^4 -46*x^3 -175*x^2 +43*x +8) / (48*x^5 -70*x^4 -126*x^3 +75*x^2 +2*x -1). - Colin Barker, May 03 2014

A223251 Two-loop graph coloring a rectangular array: number of n X 4 0..4 arrays where 0..4 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

Original entry on oeis.org

80, 1076, 17828, 307144, 5359892, 93770308, 1641741608, 28748561780, 503440061060, 8816254627208, 154390919319636, 2703707386173764, 47347570829880040, 829155025056272692, 14520239405020681988
Offset: 1

Views

Author

R. H. Hardin, Mar 18 2013

Keywords

Comments

Column 4 of A223255.

Examples

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

Crossrefs

Cf. A223255.

Formula

Empirical: a(n) = 20*a(n-1) - 28*a(n-2) - 299*a(n-3) + 436*a(n-4) + 476*a(n-5) - 460*a(n-6) for n>7.
Empirical g.f.: 4*x*(20 - 131*x - 363*x^2 + 1158*x^3 + 760*x^4 - 1036*x^5 + 24*x^6) / (1 - 20*x + 28*x^2 + 299*x^3 - 436*x^4 - 476*x^5 + 460*x^6). - Colin Barker, Aug 18 2018

A223252 Two-loop graph coloring a rectangular array: number of nX5 0..4 arrays where 0..4 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

Original entry on oeis.org

208, 4908, 166892, 5359892, 200258884, 6581646956, 247417877452, 8146965446276, 306270743418628, 10089859264898796, 379171102402141516, 12496512099428874724, 469428050069027239844, 15477220252232343414028
Offset: 1

Views

Author

R. H. Hardin Mar 18 2013

Keywords

Comments

Column 5 of A223255

Examples

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

Formula

Empirical: a(n) = 7*a(n-1) +1287*a(n-2) -8754*a(n-3) -66498*a(n-4) +293943*a(n-5) +1110271*a(n-6) -2420678*a(n-7) -6380827*a(n-8) +7393360*a(n-9) +14420088*a(n-10) -8685630*a(n-11) -12202500*a(n-12) +3405276*a(n-13) +3205824*a(n-14) -279936*a(n-15) -165888*a(n-16)

A223253 Two-loop graph coloring a rectangular array: number of nX6 0..4 arrays where 0..4 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

Original entry on oeis.org

528, 22388, 1382228, 93770308, 6581646956, 465277782336, 32969186423292, 2337308796813336, 165726502883851820, 11751198778793357708, 833253057095552710328, 59084372484837842357680, 4189562192845318714550284
Offset: 1

Views

Author

R. H. Hardin Mar 18 2013

Keywords

Comments

Column 6 of A223255

Examples

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

Formula

Empirical: a(n) = 85*a(n-1) -629*a(n-2) -31878*a(n-3) +383553*a(n-4) +1511513*a(n-5) -30275140*a(n-6) +13466360*a(n-7) +868562158*a(n-8) -1847634768*a(n-9) -9913428815*a(n-10) +32760286161*a(n-11) +38433165015*a(n-12) -223138155283*a(n-13) +39999637275*a(n-14) +633199628532*a(n-15) -503848981336*a(n-16) -699539358490*a(n-17) +910162467392*a(n-18) +144242579620*a(n-19) -523191556820*a(n-20) +110096749408*a(n-21) +74380599616*a(n-22) -21347917248*a(n-23) -1345719744*a(n-24) for n>25

A223254 Two-loop graph coloring a rectangular array: number of nX7 0..4 arrays where 0..4 label nodes of a graph with edges 0,1 1,2 2,0 0,3 3,4 4,0 and every array movement to a horizontal or vertical neighbor moves along an edge of this graph.

Original entry on oeis.org

1360, 102124, 12894316, 1641741608, 247417877452, 32969186423292, 5036570504598960, 673319614527382164, 102954418641601279556, 13767068137991538439984, 2105133349737437751454452
Offset: 1

Views

Author

R. H. Hardin Mar 18 2013

Keywords

Comments

Column 7 of A223255

Examples

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

Formula

Empirical: a(n) = 28*a(n-1) +22094*a(n-2) -612638*a(n-3) -34697699*a(n-4) +857426087*a(n-5) +19269402083*a(n-6) -452582710450*a(n-7) -5196357651810*a(n-8) +121471255123047*a(n-9) +784521840286299*a(n-10) -19032823427395385*a(n-11) -71557106240148347*a(n-12) +1891596620100268189*a(n-13) +4053226562326676303*a(n-14) -125850760507130739816*a(n-15) -137325250302977363349*a(n-16) +5810206342561348221792*a(n-17) +2112063228796457766208*a(n-18) -190673412380784423155523*a(n-19) +31175977139208452841748*a(n-20) +4519088491717666637943212*a(n-21) -2521009426787393216157164*a(n-22) -78132441653059251312771506*a(n-23) +67194762786548095348886706*a(n-24) +991114633234547769096497383*a(n-25) -1086487065817112140135963239*a(n-26) -9246978111462053478444877636*a(n-27) +11886663585913058313103682788*a(n-28) +63437992765700926323675439626*a(n-29) -91549165616667691671986180456*a(n-30) -319096012027915093663208225978*a(n-31) +505270224709833483992343060812*a(n-32) +1169834119125926599000090452428*a(n-33) -2013976920409425274563378937984*a(n-34) -3093825797818422519435176190276*a(n-35) +5806901155448165023300226112840*a(n-36) +5802724403164614446962360484208*a(n-37) -12069185782933153870041272901536*a(n-38) -7498268619479233256865142564552*a(n-39) +17928562164912874429715500178360*a(n-40) +6324408946861809730655778612160*a(n-41) -18769551482877658743060850485888*a(n-42) -3062428455340820497880529989168*a(n-43) +13571071687302027627071236968416*a(n-44) +447339093913524148546448894816*a(n-45) -6594517197317653991928731489984*a(n-46) +334978098941260036945575132544*a(n-47) +2079714767979448381582777555328*a(n-48) -203584094318775781647563314944*a(n-49) -407780845143970783852048131072*a(n-50) +48290081689441182403407559680*a(n-51) +47082942851826200463302584320*a(n-52) -5861611427120503395946905600*a(n-53) -2969668429000649309135241216*a(n-54) +367509759847220125558112256*a(n-55) +87962023235261091708665856*a(n-56) -10576877402078797696598016*a(n-57) -778809194746098437062656*a(n-58) +91689031189590139994112*a(n-59)
Showing 1-7 of 7 results.