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 13 results. Next

A220154 Number of 2 X n arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 2 X n array.

Original entry on oeis.org

6, 11, 23, 50, 88, 137, 197, 268, 350, 443, 547, 662, 788, 925, 1073, 1232, 1402, 1583, 1775, 1978, 2192, 2417, 2653, 2900, 3158, 3427, 3707, 3998, 4300, 4613, 4937, 5272, 5618, 5975, 6343, 6722, 7112, 7513, 7925, 8348, 8782, 9227, 9683, 10150, 10628
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2012

Keywords

Comments

Row 2 of A220153.

Examples

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

Crossrefs

Cf. A220153.

Formula

Empirical: a(n) = (11/2)*n^2 - (23/2)*n + 8 for n>2.
Conjectures from Colin Barker, Mar 13 2018: (Start)
G.f.: x*(6 - 7*x + 8*x^2 + 8*x^3 - 4*x^4) / (1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>5.
(End)

A220147 Number of n X 2 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 n X 2 array.

Original entry on oeis.org

3, 11, 26, 52, 95, 163, 266, 416, 627, 915, 1298, 1796, 2431, 3227, 4210, 5408, 6851, 8571, 10602, 12980, 15743, 18931, 22586, 26752, 31475, 36803, 42786, 49476, 56927, 65195, 74338, 84416, 95491, 107627, 120890, 135348, 151071, 168131, 186602
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2012

Keywords

Comments

Column 2 of A220153.

Examples

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

Crossrefs

Cf. A220153.

Formula

Empirical: a(n) = (1/12)*n^4 - (1/6)*n^3 + (29/12)*n^2 + (2/3)*n.
Conjectures from Colin Barker, Jul 30 2018: (Start)
G.f.: x*(3 - 4*x + x^2 + 2*x^3) / (1 - x)^5.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.
(End)

A220148 Number of n X 3 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 n X 3 array.

Original entry on oeis.org

6, 23, 77, 242, 727, 2062, 5493, 13773, 32664, 73654, 158660, 327852, 652215, 1253089, 2331716, 4212805, 7407330, 12701233, 21278447, 34888718, 56073127, 88463032, 137171407, 209299293, 314584340, 466223256, 681905438, 985101192
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2012

Keywords

Comments

Column 3 of A220153.

Examples

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

Crossrefs

Cf. A220153.

Formula

Empirical: a(n) = (1/19958400)*n^11 + (1/725760)*n^10 + (1/145152)*n^9 + (19/120960)*n^8 + (7/3600)*n^7 + (109/34560)*n^6 + (58081/725760)*n^5 + (26759/181440)*n^4 - (400597/907200)*n^3 + (863/126)*n^2 - (2792/495)*n + 5.
Conjectures from Colin Barker, Jul 30 2018: (Start)
G.f.: x*(6 - 49*x + 197*x^2 - 484*x^3 + 815*x^4 - 997*x^5 + 934*x^6 - 685*x^7 + 389*x^8 - 161*x^9 + 42*x^10 - 5*x^11) / (1 - x)^12.
a(n) = 12*a(n-1) - 66*a(n-2) + 220*a(n-3) - 495*a(n-4) + 792*a(n-5) - 924*a(n-6) + 792*a(n-7) - 495*a(n-8) + 220*a(n-9) - 66*a(n-10) + 12*a(n-11) - a(n-12) for n>12.
(End)

A220149 Number of nX4 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 nX4 array.

Original entry on oeis.org

10, 50, 254, 1174, 5410, 24684, 108169, 448881, 1761976, 6564622, 23314449, 79243936, 258638752, 812875058, 2465906695, 7234818015, 20565976895, 56733702403, 152106586332, 396892051129, 1009207780356, 2503839951948
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Column 4 of A220153

Examples

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

Formula

Empirical: a(n) = (1/552610124608731372158976000000)*n^29 + (1/7622208615292846512537600000)*n^28 + (1/272221736260458804019200000)*n^27 + (1/1878686930714001408000000)*n^26 + (463/23266815064996478976000000)*n^25 + (127/372269041039943663616000)*n^24 + (97193/2443015581824630292480000)*n^23 + (1458253/2124361375499678515200000)*n^22 + (293509/55178217545446195200000)*n^21 + (1203901/1051013667532308480000)*n^20 + (19197187/20232013099996938240000)*n^19 - (215771663/10648427947366809600000)*n^18 + (47996570583761/2907020829631139020800000)*n^17 - (3130777943459/13680098021793595392000)*n^16 + (352784890291/174491046196346880000)*n^15 + (12242591085947/145409205163622400000)*n^14 - (2308802430337703/1064842794736680960000)*n^13 + (63970460933829533/2129685589473361920000)*n^12 - (7607446827742849/82297057418634240000)*n^11 - (845289139000912665797/289685642113592524800000)*n^10 + (16663286001178049022791/284512684218706944000000)*n^9 - (300232887874952342719/602143247023718400000)*n^8 + (10527514392059792417183/6059066423176166400000)*n^7 + (113898768509462767685501/13464592051502592000000)*n^6 - (19927257308688059839763/149570053306486312500)*n^5 + (32438984170527374840711/44394125966910720000)*n^4 - (955894333256214244573/455832543410244000)*n^3 + (2762815941001472611/964724959598400)*n^2 - (432088153285363/1164544781400)*n - 2315 for n>4

A220150 Number of n X 5 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 n X 5 array.

Original entry on oeis.org

15, 88, 645, 4559, 34959, 279304, 2173203, 16032779, 111800304, 739040657, 4649261872, 27940861285, 160944594371, 891059955504, 4752920160872, 24475451373463, 121902117207744, 588193576732660, 2753698006392772
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Column 5 of A220153.

Examples

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

Crossrefs

Cf. A220153.

A220151 Number of nX6 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 nX6 array.

Original entry on oeis.org

21, 137, 1413, 16110, 214767, 3057777, 42648602, 564936966, 7083618786, 84318189822, 956390845855, 10375891940786, 108038550060777, 1082857046843897, 10473029871107227, 97945268899475975, 887304577889584770
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Column 6 of A220153

Examples

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

A220155 Number of 3Xn arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 3Xn array.

Original entry on oeis.org

10, 26, 77, 254, 645, 1413, 2841, 5412, 9905, 17565, 30369, 51437, 85641, 140477, 227277, 362851, 571663, 888660, 1362889, 2062054, 3078183, 4534594, 6594369, 9470566, 13438421, 18849815, 26150305, 35899043, 48791933, 65688403, 87642197
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Row 3 of A220153

Examples

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

Formula

Empirical: a(n) = (1/362880)*n^9 + (1/40320)*n^8 - (11/60480)*n^7 - (49/2880)*n^6 + (10837/17280)*n^5 - (30473/5760)*n^4 + (1003267/45360)*n^3 + (41353/3360)*n^2 - (594077/2520)*n + 361 for n>6

A220156 Number of 4Xn arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 4Xn array.

Original entry on oeis.org

15, 52, 242, 1174, 4559, 16110, 53947, 173732, 539903, 1620236, 4698464, 13180052, 35802185, 94277039, 240952485, 598495844, 1446788180, 3408685943, 7838407335, 17616947657, 38749982170, 83520468048, 176604065342, 366743870453
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Row 4 of A220153

Examples

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

Formula

Empirical: a(n) = (1/969450627708186624000000)*n^25 - (1/4562120600979701760000)*n^24 + (2027/77556050216654929920000)*n^23 - (331/177473799122780160000)*n^22 + (5539/80669908692172800000)*n^21 + (5921/3128016867655680000)*n^20 - (18577907/38318206628782080000)*n^19 + (18754471/474528874659840000)*n^18 - (41570691557/20167477173043200000)*n^17 + (5382522617/73004442255360000)*n^16 - (17042278220257/10439635242516480000)*n^15 + (9851672121271/1491376463216640000)*n^14 + (58162480943607049/52198176212582400000)*n^13 - (135094442095532831/2609908810629120000)*n^12 + (635574550376155319/474528874659840000)*n^11 - (1347751237421517133/59316109332480000)*n^10 + (296554709147396003149/1260467323315200000)*n^9 - (2610520959289132961/4236864952320000)*n^8 - (80984035976231237377421/3193183885731840000)*n^7 + (22349422485612993076363/44349776190720000)*n^6 - (7737663764129137016063569/1524523556556000000)*n^5 + (3378006014145622282711/109727291520000)*n^4 - (83444980373091022514603/820211504112000)*n^3 + (294465474881972180993/4365271310400)*n^2 + (987245448964903837/1487285800)*n - 1630947583 for n>18

A220146 Number of n X n arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 n X n array.

Original entry on oeis.org

3, 11, 77, 1174, 34959, 3057777, 822242009, 671848868714
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Diagonal of A220153

Examples

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

A220152 Number of nX7 arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 nX7 array.

Original entry on oeis.org

28, 197, 2841, 53947, 1272216, 32566283, 822242009, 19788620178, 451988194616, 9825625746882, 204030760833450, 4061291243187050, 77745303520858839, 1435301691794275091
Offset: 1

Views

Author

R. H. Hardin Dec 06 2012

Keywords

Comments

Column 7 of A220153

Examples

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