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 1-9 of 9 results.

A185512 Number of (n+1)X(n+1) 0..2 arrays with every 2X2 subblock singular.

Original entry on oeis.org

31, 1489, 154561, 80761059, 96865190255, 525819969687473, 7163899183570889649, 401495654334865659721795, 61022067811287778788163474527, 35442207739725827931704064596045201
Offset: 1

Views

Author

R. H. Hardin Jan 29 2011

Keywords

Comments

Diagonal of A185521

Examples

			Some solutions for 3X3
..0..1..1....0..0..2....2..1..2....1..0..1....0..0..2....1..0..2....1..0..0
..0..0..0....2..0..2....0..0..0....0..0..1....1..0..2....2..0..0....2..0..2
..2..2..1....2..0..0....0..2..0....1..0..0....1..0..0....2..0..1....2..0..1

A185513 Number of (n+1) X 2 0..2 arrays with every 2 X 2 subblock singular.

Original entry on oeis.org

31, 143, 593, 2553, 10847, 46303, 197329, 841449, 3587359, 15295151, 65211089, 278030937, 1185395807, 5053987327, 21547889233, 91870352457, 391693178911, 1670000659151, 7120119353681, 30356933960889, 129428088631391
Offset: 1

Views

Author

R. H. Hardin, Jan 29 2011

Keywords

Comments

Column 1 of A185521.

Examples

			Some solutions for 3 X 2:
..0..2....0..0....2..1....0..1....2..0....1..0....1..2....2..0....1..1....1..0
..0..0....0..1....2..1....0..0....0..0....1..0....0..0....0..0....0..0....2..0
..1..0....0..2....0..0....1..1....0..2....1..0....0..1....0..0....1..2....2..0

Links

Crossrefs

Cf. A185521.

Formula

Empirical: a(n) = 4*a(n-1) + 3*a(n-2) - 8*a(n-3).
Empirical g.f.: x*(31 + 19*x - 72*x^2) / (1 - 4*x - 3*x^2 + 8*x^3). - Colin Barker, Apr 16 2018

A185514 Number of (n+1) X 3 0..2 arrays with every 2 X 2 subblock singular.

Original entry on oeis.org

143, 1489, 12361, 115979, 1058503, 9856209, 91539073, 853020411, 7948563615, 74110312433, 691029158489, 6444134240459, 60095780277207, 560446106259121, 5226693550531025, 48744151344694907, 454588941498687343
Offset: 1

Views

Author

R. H. Hardin, Jan 29 2011

Keywords

Comments

Column 2 of A185521.

Examples

			Some solutions for 5 X 3:
..0..0..2....2..0..1....0..0..2....1..0..2....2..0..0....2..0..0....0..1..2
..0..0..1....2..0..2....2..0..2....1..0..1....1..0..1....2..0..2....0..0..0
..0..0..1....2..0..2....0..0..0....1..0..0....1..0..1....2..0..0....1..2..2
..1..0..0....1..0..1....0..0..2....2..0..1....0..0..0....0..0..1....0..0..0
..1..0..2....0..0..2....0..0..1....1..0..0....1..1..2....0..0..2....1..1..2

Links

Crossrefs

Cf. A185521.

Formula

Empirical: a(n) = 12*a(n-1) - 11*a(n-2) - 154*a(n-3) + 224*a(n-4).
Empirical g.f.: x*(143 - 227*x - 3934*x^2 + 6048*x^3) / (1 - 12*x + 11*x^2 + 154*x^3 - 224*x^4). - Colin Barker, Apr 16 2018

A185515 Number of (n+1) X 4 0..2 arrays with every 2 X 2 subblock singular.

Original entry on oeis.org

593, 12361, 154561, 2490449, 35659489, 541370505, 7998109489, 119752453041, 1781802607473, 26592505725449, 396308610878561, 5910310463665361, 88113720913502145, 1313850510428863561, 19589143573382779985
Offset: 1

Views

Author

R. H. Hardin, Jan 29 2011

Keywords

Comments

Column 3 of A185521.

Examples

			Some solutions for 3 X 4:
..1..1..1..2....1..2..1..2....1..2..2..2....2..0..2..1....2..0..0..1
..0..0..0..0....0..0..0..0....0..0..0..0....2..0..0..0....2..0..0..1
..0..1..0..0....1..2..0..2....1..0..1..0....2..0..2..2....2..0..0..2

Links

Crossrefs

Cf. A185521.

Formula

Empirical: a(n) = 21*a(n-1) - 47*a(n-2) - 1009*a(n-3) + 5624*a(n-4) - 3060*a(n-5) - 27360*a(n-6) + 36864*a(n-7).
Empirical g.f.: x*(593 - 92*x - 77149*x^2 + 423972*x^3 - 238356*x^4 - 2179296*x^5 + 2985984*x^6) / (1 - 21*x + 47*x^2 + 1009*x^3 - 5624*x^4 + 3060*x^5 + 27360*x^6 - 36864*x^7). - Colin Barker, Apr 16 2018

A185516 Number of (n+1)X5 0..2 arrays with every 2X2 subblock singular.

Original entry on oeis.org

2553, 115979, 2490449, 80761059, 2183297449, 65652458491, 1894624012417, 56140705014995, 1649002255383641, 48754926946880491, 1438991178016735921, 42542454880958044611, 1257346657004360967433, 37177308864717054716635
Offset: 1

Views

Author

R. H. Hardin Jan 29 2011

Keywords

Comments

Column 4 of A185521

Examples

			Some solutions for 3X5
..2..1..2..1..0....0..0..0..2..1....1..0..2..2..2....0..2..1..1..1
..0..0..0..0..0....1..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..0..1..0..1..1....0..0..0..1..0....0..0..2..1..2....2..2..1..1..1

Links

Formula

Empirical: a(n)=61*a(n-1)-1038*a(n-2)-2374*a(n-3)+235515*a(n-4)-2269967*a(n-5)+4091988*a(n-6)+57111048*a(n-7)-371380096*a(n-8)+662678992*a(n-9)+937755776*a(n-10)-4856175360*a(n-11)+5080858624*a(n-12)+506806272*a(n-13)-2361655296*a(n-14)

A185517 Number of (n+1)X6 0..2 arrays with every 2X2 subblock singular.

Original entry on oeis.org

10847, 1058503, 35659489, 2183297449, 96865190255, 5157904182519, 249246507105681, 12721664424927033, 630667351622299519, 31779395697846344999, 1587432658714531328833, 79681759021406117870025
Offset: 1

Views

Author

R. H. Hardin Jan 29 2011

Keywords

Comments

Column 5 of A185521

Examples

			Some solutions for 3X6
..0..0..0..0..0..0....0..0..1..2..1..1....1..0..0..0..2..1....0..0..2..1..0..2
..0..2..0..0..0..2....0..0..0..0..0..0....0..0..0..0..0..0....0..0..0..0..0..1
..0..0..0..2..0..2....0..1..0..1..1..1....0..1..1..1..1..2....0..1..0..2..0..0

Links

Formula

Empirical: a(n)=124*a(n-1)-4828*a(n-2)+9640*a(n-3)+4211198*a(n-4)-108674648*a(n-5)+428321452*a(n-6)+23596172360*a(n-7)-388971416381*a(n-8)+572244355004*a(n-9)+40557598916624*a(n-10)-386088931978704*a(n-11)+8157694824096*a(n-12)+19937500201681088*a(n-13)-107256141951991808*a(n-14)-112420856782623488*a(n-15)+3046625671768687360*a(n-16)-9264406533882734592*a(n-17)-12424668477383446528*a(n-18)+137806999333441568768*a(n-19)-276536454577537679360*a(n-20)-125316061156482220032*a(n-21)+1408091287365347180544*a(n-22)-2387876314993964089344*a(n-23)+1658731722007080075264*a(n-24)-273671360333161168896*a(n-25)-124425274583131619328*a(n-26)

A185518 Number of (n+1)X7 0..2 arrays with every 2X2 subblock singular.

Original entry on oeis.org

46303, 9856209, 541370505, 65652458491, 5157904182519, 525819969687473, 46861672135881249, 4536327635584899147, 421714260065729709743, 40230435280135273840049, 3792362066556802880530649
Offset: 1

Views

Author

R. H. Hardin Jan 29 2011

Keywords

Comments

Column 6 of A185521

Examples

			Some solutions for 3X7
..0..0..0..0..0..0..2....0..0..2..1..0..0..1....0..0..2..2..0..1..0
..0..2..0..1..2..0..2....0..0..0..0..0..0..0....0..0..0..0..0..0..0
..0..0..0..1..2..0..2....0..0..0..0..0..1..0....0..0..1..2..1..1..0

Links

A185519 Number of (n+1)X8 0..2 arrays with every 2X2 subblock singular.

Original entry on oeis.org

197329, 91539073, 7998109489, 1894624012417, 249246507105681, 46861672135881249, 7163899183570889649, 1241739109392066416737, 200179355912933753165009, 33717771304641221699901697
Offset: 1

Views

Author

R. H. Hardin Jan 29 2011

Keywords

Comments

Column 7 of A185521

Examples

			Some solutions for 3X8
..0..0..0..0..1..1..0..2....0..0..1..0..1..1..2..0....0..0..0..0..2..0..1..0
..0..0..0..0..0..0..0..2....0..0..0..0..0..0..0..0....0..0..0..0..0..0..0..0
..0..0..0..2..1..1..0..0....0..0..1..1..1..0..1..2....0..0..1..1..2..0..0..2

Links

A185520 Number of (n+1)X9 0..2 arrays with every 2X2 subblock singular.

Original entry on oeis.org

841449, 853020411, 119752453041, 56140705014995, 12721664424927033, 4536327635584899147, 1241739109392066416737, 401495654334865659721795, 118095161592668358071069961, 36895636527963491594862394779
Offset: 1

Views

Author

R. H. Hardin Jan 29 2011

Keywords

Comments

Column 8 of A185521

Examples

			Some solutions for 3X9
..0..0..0..0..0..0..2..0..0....0..0..0..0..2..0..0..1..1
..0..0..0..0..0..0..0..0..1....0..0..0..0..0..0..0..0..0
..0..0..0..0..0..2..0..0..0....0..0..1..0..0..0..1..1..1

Links

Showing 1-9 of 9 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement.