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 1-10 of 12 results. Next

A195213 Number of lower triangles of an n X n integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by 1 or less and triangles differing by a constant counted only once.

Original entry on oeis.org

1, 7, 91, 2277, 111031, 10654607, 2021888119, 761408842173, 570411420721871, 851650667866314005, 2537743716708476573853, 15108768742290768272235707, 179885152873727967922701202921, 4286156683596201247493358770260469
Offset: 1

Views

Author

R. H. Hardin Sep 13 2011

Keywords

Comments

Column 1 of A195220

Examples

			Some solutions for n=5
...0...............0...............0...............0...............0
...1..0...........-1.-1...........-1..0...........-1..0............1..1
...0..0..1........-2.-2.-1........-1..0..1.........0..0.-1.........0..1..0
...0..1..1..1.....-1.-1.-1.-2......0..0..0..1......1..0.-1.-2......0..1..1..0
...1..0..1..0..0..-1.-1.-2.-1.-2...0..0..1..1..2...1..0.-1.-2.-1...0..0..1..1..0
		

A195214 Number of lower triangles of an n X n integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by 2 or less and triangles differing by a constant counted only once.

Original entry on oeis.org

1, 19, 1047, 176471, 92031109, 149824887097, 764465228592699, 12257873230432791803, 618761146282316127586145, 98449515559059678433241253935, 49416410864494101822050533251357921
Offset: 1

Views

Author

R. H. Hardin Sep 13 2011

Keywords

Comments

Column 2 of A195220

Examples

			Some solutions for n=5
...0...............0...............0...............0...............0
...2..1...........-2.-1............1..0............0..1............0..1
...0..2..2.........0..0.-1.........0..2..2........-1..1..3.........1..0..0
...2..1..2..1......2..1..1..1......1..1..1..0......1..1..2..1.....-1.-1..1..2
...2..0..1..2..0...1..0..1..3..1...3..3..1..0..1...2..0..2..0..2..-2..0..0..2..2
		

A195221 Number of lower triangles of a 3 X 3 integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by n or less and triangles differing by a constant counted only once.

Original entry on oeis.org

91, 1047, 5453, 18903, 51205, 117585, 239891, 447797, 780007, 1285459, 2024529, 3070235, 4509441, 6444061, 8992263, 12289673, 16490579, 21769135, 28320565, 36362367, 46135517, 57905673, 71964379, 88630269, 108250271, 131200811
Offset: 1

Views

Author

R. H. Hardin, Sep 13 2011

Keywords

Comments

Row 3 of A195220.

Examples

			Some solutions for n=5:
  0         0         0         0         0         0         0         0
  3  0      4  4      2  1     -5 -3     -4 -2     -4 -1     -1 -5      3  3
  0 -1 -2  -1 -1  4  -3  1 -2  -5 -4  0  -6 -6 -5   1  0 -4  -2 -5-10   8  4  8
		

Crossrefs

Cf. A195220.

Formula

Empirical: a(n) = (301/30)*n^5 + (301/12)*n^4 + (88/3)*n^3 + (227/12)*n^2 + (199/30)*n + 1.
Empirical g.f.: x*(91 + 501*x + 536*x^2 + 70*x^3 + 7*x^4 - x^5) / (1 - x)^6. - Colin Barker, May 06 2018
Since a(n) is an Ehrhart polynomial of degree 5 (see A195220), and the empirical polynomial fits the Data for 1 <= n <= 6, it must be correct. - Robert Israel, Oct 06 2019

A195222 Number of lower triangles of a 4 X 4 integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by n or less and triangles differing by a constant counted only once.

Original entry on oeis.org

2277, 176471, 3395245, 31640829, 189677411, 845613769, 3048698613, 9369900047, 25430520379, 62478288201, 141479051231, 299315365855, 597820942629, 1136532061199, 2070203713171, 3632319367413, 6166018879097, 10164079181491
Offset: 1

Views

Author

R. H. Hardin, Sep 13 2011

Keywords

Comments

Row 4 of A195220.

Examples

			Some solutions for n=5:
   0            0            0            0            0            0
  -5 -2         4  5         0  3         5  2        -4 -4         1 -4
  -2 -6 -1      0  3  2      5  0  5      3  0 -3     -5 -2 -1     -3  1 -2
  -3 -1 -6 -1   3  2  5  7   4  4  2  4   3  2  0  1  -7 -2 -6 -4   0 -2 -3 -6
		

Crossrefs

Cf. A195220.

Formula

Empirical: a(n) = (1207573/30240)*n^9 + (1207573/6720)*n^8 + (1000157/2520)*n^7 + (264247/480)*n^6 + (754417/1440)*n^5 + (338651/960)*n^4 + (2533393/15120)*n^3 + (90763/1680)*n^2 + (901/84)*n + 1.
Since a(n) is an Ehrhart polynomial of degree 9 (see A195220), and the empirical polynomial fits the Data for 1 <= n <= 10, it must be correct. - Robert Israel, Oct 06 2019

A195223 Number of lower triangles of a 5 X 5 integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by n or less and triangles differing by a constant counted only once.

Original entry on oeis.org

111031, 92031109, 9032683465, 289301569283, 4677360495205, 47764170577925, 350767341744137, 2010235691940497, 9496465116615081, 38429133040711965, 136997589911672127, 439401533118090493, 1288688520518224397
Offset: 1

Views

Author

R. H. Hardin, Sep 13 2011

Keywords

Comments

Row 5 of A195220.

Examples

			Some solutions for n=5:
  0               0               0               0               0
  2  4            5  2            3  3            1  5            1  4
  7  2  3         1  5  6         5  7  6         2  3  2        -1  0 -1
  5  4  3  7      2  4  1  1      3  8  7  3      5  6  3  0      0  3  0  2
  6  5  6  2  5   5  3  6  3  1   5  3  5  6  2   9  7  2  0  0   5  3 -1  4  3
		

Crossrefs

Cf. A195220.

Formula

Empirical: a(n) = (3508493543/18345600)*n^14 + (3508493543/2620800)*n^13 + (1116775769537/239500800)*n^12 + (422094048023/39916800)*n^11 + (377328209183/21772800)*n^10 + (78475421219/3628800)*n^9 + (1073748492569/50803200)*n^8 + (19848770813/1209600)*n^7 + (221251862417/21772800)*n^6 + (18121075223/3628800)*n^5 + (10435002133/5443200)*n^4 + (505904317/907200)*n^3 + (8793472607/75675600)*n^2 + (1397863/90090)*n + 1.
Since a(n) is an Ehrhart polynomial of degree 14 (see A195220), and the empirical polynomial fits the Data for 1 <= n <= 15, it must be correct. - Robert Israel, Oct 06 2019

A195224 Number of lower triangles of a 6 X 6 integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by n or less and triangles differing by a constant counted only once.

Original entry on oeis.org

10654607, 149824887097, 103565705397639, 14572563308953245, 774355028021195459, 21369796486647028143, 368448539594713382337, 4459232627488479738855, 40959753617162679435381, 301639473232633417395629
Offset: 1

Views

Author

R. H. Hardin, Sep 13 2011

Keywords

Comments

Row 6 of A195220.
a(n) is an Ehrhart polynomial of degree 20. - Robert Israel, Oct 07 2019

Examples

			Some solutions for n=5:
   0                  0                  0                  0
   1  1              -5 -3              -3 -4               3  2
   2  1  2           -1 -1 -5           -1 -1 -2            6  5  1
   4  0  3  0        -1 -2 -1 -5         4  2  0 -2         6  1  2 -2
   3 -1  4  4  1      0  1 -1 -3 -4     -1  4  2 -2 -5      1  2  1  0 -4
   0 -1  4  1  5  5   1 -4  1  0  1 -2  -1  2  1  0 -2 -5  -2  0  3 -1 -5 -3
		

A195225 Number of lower triangles of a 7X7 integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by n or less and triangles differing by a constant counted only once.

Original entry on oeis.org

2021888119, 764465228592699, 5137554141710397313, 4059527861103273129317, 863969905606597340602967, 76019997788404353762724447, 3546881146489163009435488735, 102667264655001518661047239817
Offset: 1

Views

Author

R. H. Hardin, Sep 13 2011

Keywords

Comments

Row 7 of A195220
a(n) is an Ehrhart polynomial of degree 27. - Robert Israel, Oct 07 2019

Examples

			Some solutions for n=5
...0.....................0.....................0
...3..5..................5..0.................-3.-3
...7..8..9...............5..3..2..............-2..0.-1
...5..7..4..4............8..4.-1.-2...........-4.-4.-2..1
...6..4..4.-1.-1.........3..3.-1..0.-4........-6.-1.-1.-3..1
...1..4..2.-1..4..2......3..1.-2.-2.-3.-3.....-4.-4.-2.-4.-2..3
...6..3..4..0..4..6..3...4..3..0..1.-1.-2.-1..-1..1.-3.-3.-2..0.-2
		

A195215 Number of lower triangles of an n X n integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by 3 or less and triangles differing by a constant counted only once.

Original entry on oeis.org

1, 37, 5453, 3395245, 9032683465, 103565705397639, 5137554141710397313, 1105495964728300359472149, 1033611648181176182212080096433, 4204060119607140359160709072654583501
Offset: 1

Views

Author

R. H. Hardin Sep 13 2011

Keywords

Comments

Column 3 of A195220

Examples

			Some solutions for n=5
...0...............0...............0...............0...............0
..-3.-1............3..0...........-1.-1............0..3............2..1
..-1.-2.-2.........2..1..3.........2.-1.-4.........1..2..4.........3..3..4
...1..0..0.-3.....-1..2..3..2.....-1.-1.-2.-5......3..3..1..1......3..1..3..5
...3..0.-2.-1..0...1..0..2..1..0...0.-2.-2.-2.-3...2..0..1..2.-1...2..0..3..5..7
		

A195216 Number of lower triangles of an n X n integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by 4 or less and triangles differing by a constant counted only once.

Original entry on oeis.org

1, 61, 18903, 31640829, 289301569283, 14572563308953245, 4059527861103273129317, 6270118871204192400242141667, 53785756580019628016324622812810239
Offset: 1

Views

Author

R. H. Hardin Sep 13 2011

Keywords

Comments

Column 4 of A195220

Examples

			Some solutions for n=5
...0...............0...............0...............0...............0
..-4.-3...........-4.-4............4..4............3..1............2..1
..-6.-2.-5........-7.-3..0.........2..1..3.........3.-1.-1........-1..1..1
..-5.-5.-2.-4.....-4.-4.-1.-2......3..5..5..4......1..3..0.-4.....-3.-3.-1.-1
..-6.-4.-4.-5.-7..-5.-5.-2.-4.-3...2..2..1..5..8...2..3..0.-2.-2..-3.-1.-1..0..0
		

A195217 Number of lower triangles of an n X n integer array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by 5 or less and triangles differing by a constant counted only once.

Original entry on oeis.org

1, 91, 51205, 189677411, 4677360495205, 774355028021195459, 863969905606597340602967, 6512935591253221256126051469607
Offset: 1

Views

Author

R. H. Hardin Sep 13 2011

Keywords

Comments

Column 5 of A195220

Examples

			Some solutions for n=5
...0...............0...............0...............0...............0
...3..3............2.-2...........-1.-2...........-3..0............4..1
...2..0..4.........0..3.-1.........1..3.-1.........0..2..3.........6..2..5
..-2..0..2..1......1.-2.-1.-5......5..2..2.-2.....-3.-2.-2.-1......3..5..6..8
...0..3..0.-1..3...0.-1.-5..0.-3...3..1.-2.-3..2...1..0..0.-1.-3...6..5..6..3..3
		
Showing 1-10 of 12 results. Next