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 11 results. Next

A266930 Number of n X 3 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

2, 4, 9, 20, 44, 92, 182, 340, 605, 1028, 1680, 2651, 4058, 6045, 8793, 12518, 17484, 24001, 32438, 43222, 56853, 73901, 95024, 120965, 152570, 190786, 236681, 291440, 356388, 432986, 522854, 627768, 749685, 890738, 1053264, 1239799, 1453106
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Examples

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

Crossrefs

Column 3 of A266935.

Formula

Empirical: a(n) = 4*a(n-1) - 4*a(n-2) - 3*a(n-3) + 6*a(n-4) - 6*a(n-7) + 3*a(n-8) + 4*a(n-9) - 4*a(n-10) + a(n-11).
Empirical g.f.: x*(2 - 4*x + x^2 + 6*x^3 - x^5 - 4*x^6 + 4*x^7 + 3*x^8 - 4*x^9 + x^10) / ((1 - x)^7*(1 + x)^2*(1 + x + x^2)). - Colin Barker, Jan 10 2019.

A266931 Number of n X 4 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

2, 5, 12, 35, 100, 288, 794, 2077, 5110, 11869, 26086, 54543, 108999, 209148, 386883, 692473, 1203061, 2034487, 3357115, 5416951, 8563297, 13284702, 20254831, 30390893, 44926915, 65505045, 94288435, 134099783, 188589873, 262441858
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Comments

Column 4 of A266935.

Examples

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

Crossrefs

Cf. A266935.

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) -4*a(n-3) -9*a(n-4) -a(n-5) +19*a(n-6) +13*a(n-7) -13*a(n-8) -25*a(n-9) -11*a(n-10) +15*a(n-11) +22*a(n-12) +17*a(n-13) -4*a(n-14) -23*a(n-15) -23*a(n-16) -4*a(n-17) +17*a(n-18) +22*a(n-19) +15*a(n-20) -11*a(n-21) -25*a(n-22) -13*a(n-23) +13*a(n-24) +19*a(n-25) -a(n-26) -9*a(n-27) -4*a(n-28) +3*a(n-29) +2*a(n-30) -a(n-31).

A266932 Number of nX5 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

2, 5, 14, 52, 210, 871, 3566, 13899, 50841, 173470, 553021, 1652621, 4652572, 12400392, 31443461, 76188169, 177120011, 396481264, 857322183, 1795814448, 3653191802, 7233526075, 13969016501, 26357103244, 48668165412, 88071764221
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Comments

Column 5 of A266935.

Examples

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

Crossrefs

Cf. A266935.

A266936 Number of 3 X n binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

4, 7, 9, 12, 14, 19, 21, 26, 30, 35, 39, 46, 50, 57, 63, 70, 76, 85, 91, 100, 108, 117, 125, 136, 144, 155, 165, 176, 186, 199, 209, 222, 234, 247, 259, 274, 286, 301, 315, 330, 344, 361, 375, 392, 408, 425, 441, 460, 476, 495, 513, 532, 550, 571, 589, 610, 630, 651, 671
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Examples

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

Crossrefs

Row 3 of A266935.

Formula

Empirical: a(n) = a(n-1) + a(n-2) - a(n-4) - a(n-5) + a(n-6).
Empirical g.f.: x*(4 + 3*x - 2*x^2 - 4*x^3 - 3*x^4 + 4*x^5) / ((1 - x)^3*(1 + x)*(1 + x + x^2)). - Colin Barker, Jan 10 2019

A266937 Number of 4 X n binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

5, 12, 20, 35, 52, 82, 115, 169, 232, 322, 426, 573, 738, 961, 1215, 1543, 1912, 2382, 2905, 3557, 4280, 5161, 6135, 7308, 8594, 10120, 11791, 13749, 15883, 18361, 21049, 24142, 27490, 31307, 35427, 40093, 45111, 50757, 56818, 63594, 70848, 78917, 87535
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Examples

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

Crossrefs

Row 4 of A266935.

Formula

Empirical: a(n) = a(n-1) + 2*a(n-2) - a(n-3) - a(n-4) - a(n-5) - a(n-6) + 2*a(n-8) + 2*a(n-9) - a(n-11) - a(n-12) - a(n-13) - a(n-14) + 2*a(n-15) + a(n-16) -a(n-17).
Empirical g.f.: x*(5 + 7*x - 2*x^2 - 4*x^3 - 6*x^4 - 3*x^5 + x^6 + 9*x^7 + 12*x^8 + 2*x^9 -6*x^10 - 4*x^11 - 6*x^12 - 5*x^13 + 9*x^14 + 6*x^15 - 5*x^16) / ((1 - x)^6*(1 + x)^3*(1 + x^2)*(1 + x + x^2)*(1 + x + x^2 + x^3 + x^4)). - Colin Barker, Jan 10 2019

A266938 Number of 5Xn binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

6, 19, 44, 100, 210, 429, 816, 1534, 2727, 4753, 7931, 13044, 20676, 32360, 49327, 73959, 108612, 157751, 224746, 317514, 440564, 606496, 823905, 1110469, 1480403, 1957027, 2563177, 3335398, 4302564, 5520403, 7021711, 8888187, 11173884
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Comments

Row 5 of A266935.

Examples

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

Crossrefs

Cf. A266935.

A266929 Number of n X n binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

2, 4, 9, 35, 210, 2577, 68890, 4605960, 821453747
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Comments

Diagonal of A266935.

Examples

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

Crossrefs

Cf. A266935.

A266933 Number of nX6 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

2, 6, 19, 82, 429, 2577, 15850, 96503, 555060, 2977370, 14782970, 68041108, 291292442, 1165800099, 4383605127, 15564591521, 52423001756, 168200350788, 516045791503, 1519124991181
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Comments

Column 6 of A266935.

Examples

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

Crossrefs

Cf. A266935.

A266934 Number of nX7 binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

2, 6, 21, 115, 816, 7185, 68890, 671796, 6347005, 56180274, 460040399, 3470013146, 24151911854, 155703390684
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Comments

Column 7 of A266935.

Examples

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

Crossrefs

Cf. A266935.

A266939 Number of 6Xn binary arrays with rows lexicographically nondecreasing and columns lexicographically nondecreasing and row sums nondecreasing and column sums nonincreasing.

Original entry on oeis.org

7, 29, 92, 288, 871, 2577, 7185, 19529, 50216, 125786, 298869, 696808, 1546941, 3382516, 7085876, 14650326, 29153966, 57417292, 109223923, 205966389, 376634957, 683318087, 1206075185, 2114385852, 3615867548
Offset: 1

Views

Author

R. H. Hardin, Jan 06 2016

Keywords

Comments

Row 6 of A266935.

Examples

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

Crossrefs

Cf. A266935.
Showing 1-10 of 11 results. Next