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 1-5 of 5 results.

A241125 Number of n X 2 0..2 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..2 introduced in row major order.

Original entry on oeis.org

2, 9, 54, 325, 1965, 11876, 71793, 434007, 2623694, 15861001, 95884409, 579649484, 3504151829, 21183629803, 128061281038, 774168159805, 4680074530261, 28292428888436, 171036065180937, 1033963386740399, 6250613190784174
Offset: 1

Views

Author

R. H. Hardin, Apr 16 2014

Keywords

Examples

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

Crossrefs

Column 2 of A241130.

Formula

Empirical: a(n) = 6*a(n-1) + 2*a(n-2) - 9*a(n-3) - 10*a(n-4) + 8*a(n-5) for n>6.
Empirical g.f.: x*(1 - x)*(1 - 2*x)*(2 + 3*x + x^2 - 2*x^3) / (1 - 6*x - 2*x^2 + 9*x^3 + 10*x^4 - 8*x^5). - Colin Barker, Oct 29 2018

A241126 Number of nX3 0..2 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..2 introduced in row major order.

Original entry on oeis.org

4, 54, 723, 9773, 132369, 1792237, 24269723, 328645291, 4450319537, 60263615333, 816054461063, 11050530322615, 149639792084929, 2026334190350265, 27439427668181531, 371568616043522567, 5031563999805819365
Offset: 1

Views

Author

R. H. Hardin, Apr 16 2014

Keywords

Comments

Column 3 of A241130

Examples

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

Formula

Empirical: a(n) = 14*a(n-1) -7*a(n-2) +27*a(n-3) -170*a(n-4) -631*a(n-5) -1135*a(n-6) +5278*a(n-7) -3113*a(n-8) +5125*a(n-9) +13678*a(n-10) -10325*a(n-11) +15744*a(n-12) -52520*a(n-13) -13756*a(n-14) -110176*a(n-15) +64424*a(n-16) -53672*a(n-17) -13552*a(n-18) +87456*a(n-19) -198528*a(n-20) +71552*a(n-21) -44288*a(n-22) -116224*a(n-23) -4096*a(n-24) -122880*a(n-25) -65536*a(n-26)

A241127 Number of nX4 0..2 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..2 introduced in row major order.

Original entry on oeis.org

11, 325, 9773, 295584, 8974020, 272418756, 8270609664, 251096788713, 7623351508315, 231446775293031, 7026779711400192, 213334731852107120, 6476894113062087316, 196640073775126182008, 5970040263453594766199
Offset: 1

Views

Author

R. H. Hardin, Apr 16 2014

Keywords

Comments

Column 4 of A241130

Examples

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

A241128 Number of nX5 0..2 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..2 introduced in row major order.

Original entry on oeis.org

30, 1965, 132369, 8974020, 611547441, 41661463219, 2838552905280, 193403197619803, 13177423185201303, 897837461485635262, 61173728850055840649, 4168043075184317942781, 283987643903962340437622
Offset: 1

Views

Author

R. H. Hardin, Apr 16 2014

Keywords

Comments

Column 5 of A241130

Examples

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

A241129 Number of nX6 0..2 arrays with no element equal to exactly two horizontal and vertical neighbors, with new values 0..2 introduced in row major order.

Original entry on oeis.org

82, 11876, 1792237, 272418756, 41661463219, 6369134821236, 973866422990563, 148910067386335603, 22769250775360645781, 3481561098182183872590, 532352524971939702558325, 81400042312275755768027497
Offset: 1

Views

Author

R. H. Hardin, Apr 16 2014

Keywords

Comments

Column 6 of A241130

Examples

			Some solutions for n=2
..0..1..1..1..2..1....0..1..0..2..0..2....0..1..0..1..0..1....0..1..2..1..2..1
..0..2..1..0..1..0....1..0..2..0..0..0....1..0..0..0..1..2....2..2..0..0..2..0
		
Showing 1-5 of 5 results.