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 1-6 of 6 results.

A274797 Number of n X n 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) (0,-1) or (-1,0) and new values introduced in order 0..2.

Original entry on oeis.org

1, 3, 30, 596, 22988, 1774372, 273764292, 85071335388, 53278240463204, 67444355089828632, 172664716787589924632, 895256317336401964070392, 9404595196718819502562934668, 200324135427294084369446897344852
Offset: 1

Views

Author

R. H. Hardin, Jul 07 2016

Keywords

Comments

Diagonal of A274803.

Examples

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

Crossrefs

Cf. A274803.

A274798 Number of n X 3 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) (0,-1) or (-1,0) and new values introduced in order 0..2.

Original entry on oeis.org

2, 8, 30, 112, 420, 1572, 5888, 22048, 82568, 309200, 1157904, 4336144, 16238112, 60808896, 227718752, 852767104, 3193464512, 11958969152, 44784259584, 167709263104, 628042022016, 2351908141824, 8807486941952, 32982506778880
Offset: 1

Views

Author

R. H. Hardin, Jul 07 2016

Keywords

Examples

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

Crossrefs

Column 3 of A274803.

Formula

Empirical: a(n) = 2*a(n-1) + 6*a(n-2) + 2*a(n-3).
Empirical g.f.: 2*x*(1 + x)^2 / (1 - 2*x - 6*x^2 - 2*x^3). - Colin Barker, Jan 30 2019

A274799 Number of n X 4 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) (0,-1) or (-1,0) and new values introduced in order 0..2.

Original entry on oeis.org

4, 22, 112, 596, 3104, 16328, 85504, 448656, 2352080, 12335680, 64684112, 339207984, 1778768656, 9327806784, 48914391648, 256504556080, 1345094908224, 7053603314896, 36988695973168, 193966647764784, 1017150172662336
Offset: 1

Views

Author

R. H. Hardin, Jul 07 2016

Keywords

Examples

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

Crossrefs

Column 4 of A274803.

Formula

Empirical: a(n) = 2*a(n-1) + 15*a(n-2) + 11*a(n-3) - 2*a(n-4) - 2*a(n-5).
Empirical g.f.: 2*x*(2 + 7*x + 4*x^2 - x^3 - x^4) / (1 - 2*x - 15*x^2 - 11*x^3 + 2*x^4 + 2*x^5). - Colin Barker, Jan 31 2019

A274800 Number of n X 5 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) (0,-1) or (-1,0) and new values introduced in order 0..2.

Original entry on oeis.org

8, 60, 420, 3104, 22988, 169328, 1252608, 9243332, 68301192, 504334580, 3725379284, 27513045320, 203212320508, 1500856265992, 11085101613680, 81871796085532, 604688931568808, 4466096896968716, 32985652382855332
Offset: 1

Views

Author

R. H. Hardin, Jul 07 2016

Keywords

Examples

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

Crossrefs

Column 5 of A274803.

Formula

Empirical: a(n) = 2*a(n-1) + 35*a(n-2) + 42*a(n-3) - 41*a(n-4) - 60*a(n-5) - 23*a(n-6) - 2*a(n-7).
Empirical g.f.: 4*x*(2 + 11*x + 5*x^2 - 43*x^3 - 28*x^4 + 3*x^5 + 2*x^6) / (1 - 2*x - 35*x^2 - 42*x^3 + 41*x^4 + 60*x^5 + 23*x^6 + 2*x^7). - Colin Barker, Jan 31 2019

A274801 Number of n X 6 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) (0,-1) or (-1,0) and new values introduced in order 0..2.

Original entry on oeis.org

16, 164, 1572, 16328, 169328, 1774372, 18476064, 193292660, 2016460140, 21072173792, 219985654388, 2297904486000, 23995177354892, 250610794543168, 2617142836973944, 27332712382107996, 285444819027741180
Offset: 1

Views

Author

R. H. Hardin, Jul 07 2016

Keywords

Comments

Column 6 of A274803.

Examples

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

Crossrefs

Cf. A274803.

Formula

Empirical: a(n) = 2*a(n-1) +80*a(n-2) +140*a(n-3) -474*a(n-4) -998*a(n-5) -130*a(n-6) +781*a(n-7) +814*a(n-8) -79*a(n-9) -360*a(n-10) +54*a(n-11) +48*a(n-12) -52*a(n-13) +4*a(n-14) for n>15.

A274802 Number of nX7 0..2 arrays with no element equal to any value at offset (-1,-2) (-2,-1) (0,-1) or (-1,0) and new values introduced in order 0..2.

Original entry on oeis.org

32, 448, 5888, 85504, 1252608, 18476064, 273764292, 4044928780, 59936952948, 886462457880, 13127736774888, 194250101777432, 2875817749885724, 42561628448681904, 630035159343912668, 9325142535870239784
Offset: 1

Views

Author

R. H. Hardin, Jul 07 2016

Keywords

Comments

Column 7 of A274803.

Examples

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

Crossrefs

Cf. A274803.

Formula

Empirical: a(n) = 2*a(n-1) +182*a(n-2) +434*a(n-3) -4080*a(n-4) -11758*a(n-5) +15420*a(n-6) +64260*a(n-7) +38245*a(n-8) -87869*a(n-9) -225572*a(n-10) -13082*a(n-11) +255188*a(n-12) -3166*a(n-13) -19321*a(n-14) +49122*a(n-15) -82502*a(n-16) -88689*a(n-17) +115251*a(n-18) -9925*a(n-19) -4172*a(n-20) -937*a(n-21) -317*a(n-22) +140*a(n-23) -94*a(n-24) +6*a(n-25) for n>26
Showing 1-6 of 6 results.