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 1-8 of 8 results.

A229770 Number of n X n 0..2 arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order.

Original entry on oeis.org

3, 22, 322, 12958, 2179956, 1976588468, 10811999412826, 378274896023686216, 88035611475274172311886, 140618374201747733896872001960
Offset: 1

Views

Author

R. H. Hardin, Sep 29 2013

Keywords

Comments

Column 2 of A229774

Examples

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

A229771 Number of n X n 0..3 arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order.

Original entry on oeis.org

4, 60, 3232, 1058494, 3062815568, 90462380211862, 29201160476766771330, 108134253835820664368578112
Offset: 1

Views

Author

R. H. Hardin, Sep 29 2013

Keywords

Comments

Column 3 of A229774

Examples

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

A229775 Number of 3 X 3 0..n arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order.

Original entry on oeis.org

20, 322, 3232, 21331, 103222, 397460, 1287672, 3647349, 9281272, 21642038, 46934680, 95749927, 185397226, 343142248, 610590224, 1049496105, 1749325212, 2836933738, 4488787184, 6946186555, 10534026910, 15683670652, 22960578760
Offset: 1

Views

Author

R. H. Hardin, Sep 29 2013

Keywords

Examples

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

Crossrefs

Row 3 of A229774.

Formula

Empirical: a(n) = (1/120)*n^9 + (1/12)*n^8 + (133/360)*n^7 + (371/360)*n^6 + (19/9)*n^5 + (247/72)*n^4 + (403/90)*n^3 + (401/90)*n^2 + (91/30)*n + 1.
Conjectures from Colin Barker, Sep 21 2018: (Start)
G.f.: x*(20 + 122*x + 912*x^2 + 1101*x^3 + 912*x^4 - 125*x^5 + 118*x^6 - 45*x^7 + 10*x^8 - x^9) / (1 - x)^10.
a(n) = 10*a(n-1) - 45*a(n-2) + 120*a(n-3) - 210*a(n-4) + 252*a(n-5) - 210*a(n-6) + 120*a(n-7) - 45*a(n-8) + 10*a(n-9) - a(n-10) for n>10.
(End)

A229776 Number of 4X4 0..n arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order.

Original entry on oeis.org

70, 12958, 1058494, 35452250, 637396928, 7379634620, 61734072288, 402537583863, 2155573868470, 9841145888530, 39380724254950, 141067066333648, 459822149867432, 1381730749348760, 3867950992777232, 10173948824534685
Offset: 1

Views

Author

R. H. Hardin, Sep 29 2013

Keywords

Comments

Row 4 of A229774

Examples

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

Formula

Empirical: a(n) = (1/5040)*n^16 + (17/5040)*n^15 + (89/3360)*n^14 + (143/1120)*n^13 + (307/720)*n^12 + (307/288)*n^11 + (64247/30240)*n^10 + (53933/15120)*n^9 + (10645/2016)*n^8 + (71609/10080)*n^7 + (44/5)*n^6 + (14447/1440)*n^5 + (8975/864)*n^4 + (20359/2160)*n^3 + (3505/504)*n^2 + (1543/420)*n + 1

A229777 Number of 5X5 0..n arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order.

Original entry on oeis.org

252, 2179956, 3062815568, 843211336888, 81937334158292, 3896490956821414, 110102810429666544, 2093314279759590565, 29136130649614970102, 315228320642171324718, 2770642691605055402356, 20456013945849864263232
Offset: 1

Views

Author

R. H. Hardin, Sep 29 2013

Keywords

Comments

Row 5 of A229774

Examples

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

A229772 Number of n X n 0..4 arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order.

Original entry on oeis.org

5, 135, 21331, 35452250, 843211336888, 322942973130396495, 2131384087795458774515411
Offset: 1

Views

Author

R. H. Hardin, Sep 29 2013

Keywords

Comments

Column 4 of A229774

Examples

			Some solutions for n=3
..3..3..1....1..1..0....3..2..0....0..0..0....3..1..1....2..1..1....2..1..1
..3..3..4....4..2..3....4..3..2....3..2..1....4..4..2....4..1..1....4..3..1
..4..3..0....4..3..2....4..4..0....3..4..3....4..4..4....4..3..3....4..4..4
		

A229773 Number of n X n 0..5 arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order.

Original entry on oeis.org

6, 266, 103222, 637396928, 81937334158292, 245200063296427870294, 18316874320807782299001320802
Offset: 1

Views

Author

R. H. Hardin, Sep 29 2013

Keywords

Comments

Column 5 of A229774

Examples

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

A229778 Number of 6X6 0..n arrays with rows in lexicographically nondecreasing order and columns in nonincreasing order.

Original entry on oeis.org

924, 1976588468, 90462380211862, 322942973130396495, 245200063296427870294, 65350451915118676316696, 8161432175844147542615052, 573385480689864447112662651, 25636132281885860529849116700
Offset: 1

Views

Author

R. H. Hardin, Sep 29 2013

Keywords

Comments

Row 6 of A229774

Examples

			Some solutions for n=1
..0..0..0..0..0..0....1..1..1..1..1..1....1..0..0..0..0..0....1..0..0..0..0..0
..1..0..0..0..0..0....1..1..1..1..1..1....1..0..0..0..0..0....1..0..0..0..0..0
..1..1..1..0..0..0....1..1..1..1..1..1....1..0..0..0..0..0....1..0..0..0..0..0
..1..1..1..1..1..0....1..1..1..1..1..1....1..1..1..0..0..0....1..0..0..0..0..0
..1..1..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..0....1..1..0..0..0..0
..1..1..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..0....1..1..1..0..0..0
		
Showing 1-8 of 8 results.