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.

A183364 Number of n X 2 binary arrays with no element equal to the sum mod 3 of its horizontal and vertical neighbors.

Original entry on oeis.org

2, 3, 5, 12, 21, 41, 84, 171, 355, 732, 1517, 3165, 6608, 13809, 28871, 60398, 126425, 264681, 554188, 1160473, 2430233, 5089614, 10659415, 22324873, 46757436, 97930229, 205109405, 429591772, 899761459, 1884515059, 3947047760, 8266953369
Offset: 1

Views

Author

R. H. Hardin, Jan 04 2011

Keywords

Comments

Column 2 of A183368.

Examples

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

Crossrefs

Cf. A183368.

Formula

Empirical: a(n) = 2*a(n-1) + a(n-3) - 4*a(n-6) - 3*a(n-7) + a(n-10).
Empirical g.f.: x*(1 + x)*(2 - 3*x + 2*x^2 - 2*x^3 - 4*x^4 - 2*x^5 + x^8) / (1 - 2*x - x^3 + 4*x^6 + 3*x^7 - x^10). - Colin Barker, Mar 28 2018

A183365 Number of nX3 binary arrays with no element equal to the sum mod 3 of its horizontal and vertical neighbors.

Original entry on oeis.org

2, 5, 18, 39, 108, 288, 795, 2278, 6438, 18394, 52556, 150565, 431730, 1238954, 3556322, 10210036, 29317763, 84190569, 241782416, 694380738, 1994246166, 5727497628, 16449560195, 47243891395, 135686993036, 389700996218
Offset: 1

Views

Author

R. H. Hardin Jan 04 2011

Keywords

Comments

Column 3 of A183368

Examples

			Some solutions for 5X3
..1..0..1....1..1..1....0..1..1....0..0..0....1..1..0....0..1..1....1..1..0
..0..0..0....1..1..1....1..1..1....1..1..1....1..1..0....0..1..1....1..1..0
..1..1..0....0..0..0....1..0..1....1..1..1....1..1..0....0..1..1....0..0..1
..1..1..0....0..0..1....1..1..1....0..0..0....0..1..1....0..1..1....1..0..0
..0..0..1....1..0..0....1..1..0....0..1..0....0..1..1....1..0..0....0..1..0
		

Formula

Empirical: a(n)=3*a(n-1)+a(n-3)-4*a(n-4)+4*a(n-5)-22*a(n-6)-12*a(n-7)-21*a(n-8)+22*a(n-9)-13*a(n-10)+115*a(n-11)+79*a(n-12)+116*a(n-13)-45*a(n-14)+172*a(n-15)-75*a(n-16)-54*a(n-17)-181*a(n-18)-85*a(n-19)-61*a(n-20)-11*a(n-21)-158*a(n-22)+80*a(n-23)+157*a(n-24)+215*a(n-25)-78*a(n-26)-211*a(n-27)-196*a(n-28)-51*a(n-29)+44*a(n-30)+81*a(n-31)+64*a(n-32)+13*a(n-33)-13*a(n-34)-12*a(n-35)-7*a(n-36)-a(n-37)+a(n-38)+a(n-39)

A183366 Number of n X 4 binary arrays with no element equal to the sum modulo 3 of its horizontal and vertical neighbors.

Original entry on oeis.org

3, 12, 39, 138, 548, 2129, 8311, 32933, 130750, 519980, 2069494, 8238734, 32801506, 130618157, 520176813, 2071605150, 8250287558, 32857555574, 130858980239, 521161959522, 2075594388132, 8266327630092, 32921750282882, 131115278622574, 522184203094342, 2079668830404846
Offset: 1

Views

Author

R. H. Hardin, Jan 04 2011

Keywords

Examples

			Some solutions for 5 X 4:
  1 0 1 0    1 0 0 0    1 1 0 0    1 1 0 0    1 1 1 0
  0 0 0 1    0 0 1 1    1 1 0 1    1 1 0 1    1 0 1 0
  0 1 0 0    1 0 1 1    0 0 0 0    0 0 0 0    1 1 1 0
  1 0 0 1    0 0 1 1    1 1 1 0    0 1 1 1    0 0 0 0
  0 0 1 0    1 0 0 0    1 1 1 0    0 1 1 1    1 0 0 1
		

Crossrefs

Column 4 of A183368.

A183367 Number of nX5 binary arrays with no element equal to the sum mod 3 of its horizontal and vertical neighbors.

Original entry on oeis.org

4, 21, 108, 548, 3102, 17101, 95674, 543837, 3094889, 17654882, 100922299, 576885277, 3298560872, 18868606128, 107935859047, 617459322870, 3532519181939, 20210076149240, 115625671366613, 661524633792529
Offset: 1

Views

Author

R. H. Hardin Jan 04 2011

Keywords

Comments

Column 5 of A183368

Examples

			Some solutions for 7X5
..0..1..1..0..1....0..1..0..1..1....1..1..1..1..0....0..1..0..1..1
..1..1..1..0..0....0..0..0..1..1....1..0..0..1..0....1..0..0..1..1
..1..0..1..0..1....1..0..0..0..0....1..0..0..1..1....0..0..0..1..0
..1..1..1..0..0....0..0..1..1..0....1..1..1..0..1....0..1..1..1..0
..0..0..0..0..0....0..1..1..1..0....0..0..1..1..1....1..1..0..0..1
..0..0..1..1..1....1..1..0..1..1....1..0..0..0..0....1..1..0..0..0
..1..0..1..1..1....1..1..1..1..1....0..0..1..0..1....1..1..0..1..0
		

A183363 Number of n X n binary arrays with no element equal to the sum mod 3 of its horizontal and vertical neighbors.

Original entry on oeis.org

1, 3, 18, 138, 3102, 137688, 12617557, 2402945556, 936460285557, 739951660291721
Offset: 1

Views

Author

R. H. Hardin Jan 04 2011

Keywords

Comments

Diagonal of A183368

Examples

			Some solutions for 5X5
..1..0..0..1..1....1..1..1..0..0....1..1..1..1..0....1..1..0..0..1
..0..0..1..1..1....1..0..1..0..1....1..0..0..1..0....1..1..1..0..0
..1..0..1..0..1....1..1..1..0..0....1..0..0..1..1....1..0..1..1..1
..0..0..1..1..1....0..0..1..1..1....1..1..1..1..1....1..1..0..1..1
..1..0..1..1..1....1..0..1..1..1....1..1..0..0..0....0..1..1..1..0
		
Showing 1-5 of 5 results.