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 15 results. Next

A068761 Number of potential flows in n X n array with integer velocities in -14..14, i.e., number of n X n arrays with adjacent elements differing by no more than 14, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 16269, 105227044417, 278175212679968120043
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, solenoidal flows A068722-A068738.

A212195 Square array A(n,k), n>=1, k>=1, read by antidiagonals: A(n,k) is the number of n-colorings of the staggered hexagonal square grid graph SH_(k,k).

Original entry on oeis.org

1, 0, 2, 0, 0, 3, 0, 0, 6, 4, 0, 0, 6, 48, 5, 0, 0, 6, 1056, 180, 6, 0, 0, 6, 45696, 32940, 480, 7, 0, 0, 6, 4038432, 30847500, 393600, 1050, 8, 0, 0, 6, 743601024, 148046704020, 3312560640, 2735250, 2016, 9
Offset: 1

Views

Author

Alois P. Heinz, May 03 2012

Keywords

Comments

The staggered hexagonal square grid graph SH_(n,n) has n^2 = A000290(n) vertices and (n-1)*(3*n-1) = A045944(n-1) edges; see A212194 for example. The chromatic polynomial of SH_(n,n) has n^2+1 = A002522(n) coefficients.
A differs from A212163 first at (n,k) = (4,5): A(4,5) = 4038432, A212163(4,5) = 4034304.

Examples

			Square array A(n,k) begins:
  1,    0,       0,            0,                 0, ...
  2,    0,       0,            0,                 0, ...
  3,    6,       6,            6,                 6, ...
  4,   48,    1056,        45696,           4038432, ...
  5,  180,   32940,     30847500,      148046704020, ...
  6,  480,  393600,   3312560640,   286170443437440, ...
  7, 1050, 2735250, 123791435250, 97337320223288250, ...
		

Crossrefs

Columns k=1-6 give: A000027, A047927(n) = 6*A002417(n-2), 6*A068244, 6*A068245, 6*A068248, 6*A068249.
Rows n=1-10, 16-18 give: A000007, A000038, A040006, 4*A068283, 5*A068284, 6*A068285, 7*A068286, 8*A068287, 9*A068288, 10*A068289, 16*A068290, 17*A068291, 18*A068292.

A068748 Number of potential flows in n X n array with integer velocities in -1..1, i.e., number of n X n arrays with adjacent elements differing by no more than 1, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 19, 1665, 690437, 1366395515, 12961320464027, 590771311004409091, 129585582154154757804255, 136932044780329080616264070553, 697547669137459516115242710064880165
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, solenoidal flows A068722-A068738.

A068752 Number of potential flows in n X n array with integer velocities in -5..5, i.e., number of n X n arrays with adjacent elements differing by no more than 5, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 891, 45642289, 138190481342321, 24953087551680958151267
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, A068752 solenoidal flows A068722-A068738.

A068749 Number of potential flows in n X n array with integer velocities in -2..2, i.e., number of n X n arrays with adjacent elements differing by no more than 2, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 85, 87825, 1133641543, 184422574177355, 379827509377146575439, 9928923943603018785634645661
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, solenoidal flows A068722-A068738.

A068750 Number of potential flows in n X n array with integer velocities in -3..3, i.e., number of n X n arrays with adjacent elements differing by no more than 3, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 231, 1253329, 164185416899, 523957519578572209, 40918963843906494595507077
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, solenoidal flows A068722-A068738.

A068751 Number of potential flows in n X n array with integer velocities in -4..4, i.e., number of n X n arrays with adjacent elements differing by no more than 4, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 489, 9230193, 6913624013061, 207345516734034667209
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, solenoidal flows A068722-A068738.

A068753 Number of potential flows in n X n array with integer velocities in -6..6, i.e., number of n X n arrays with adjacent elements differing by no more than 6, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 1469, 172989921, 1678843050246451, 1354915464537160758459123
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, solenoidal flows A068722-A068738.

A068754 Number of potential flows in n X n array with integer velocities in -7..7, i.e., number of n X n arrays with adjacent elements differing by no more than 7, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 2255, 542131425, 14285299502131463
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, solenoidal flows A068722-A068738.

A068755 Number of potential flows in n X n array with integer velocities in -8..8, i.e., number of n X n arrays with adjacent elements differing by no more than 8, counting arrays differing by a constant only once.

Original entry on oeis.org

1, 3281, 1473095713, 93044501704039945
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2002

Keywords

Crossrefs

By size 3 X 3, ..., 6 X 6 A068744-A068747, by velocity limit 1..14 A068248-A068761, solenoidal flows A068722-A068738.
Showing 1-10 of 15 results. Next