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

A212930 T(n,k) = number of n X k 0..k-1 arrays with no column j greater than column j-1 in all rows.

Original entry on oeis.org

1, 3, 1, 10, 15, 1, 35, 568, 63, 1, 126, 39695, 18226, 255, 1, 462, 4431876, 14177855, 518320, 1023, 1, 1716, 724082352, 23124921876, 4041974015, 14230810, 4095, 1, 6435, 163050236504, 68264066143602, 85800824609376, 1075113010175, 386357608
Offset: 1

Views

Author

R. H. Hardin, May 31 2012

Keywords

Comments

Table starts
.1....3.......10............35................126......................462
.1...15......568.........39695............4431876................724082352
.1...63....18226......14177855........23124921876...........68264066143602
.1..255...518320....4041974015.....85800824609376......4051316109991426752
.1.1023.14230810.1075113010175.285912852294921876.207406617181155352354002

Examples

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

Crossrefs

Column 2 is A024036.
Row 1 is A001700(n-1).
Cf. A212943.

Formula

Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = 5*a(n-1) -4*a(n-2)
k=3: a(n) = 37*a(n-1) -279*a(n-2) +243*a(n-3)
k=4: a(n) = 405*a(n-1) -43860*a(n-2) +1524160*a(n-3) -15636480*a(n-4) +14155776*a(n-5)
The coefficient of a(n-1) is A209671(k) (through at least k=1..7)

A212937 Number of n X n 0..n-1 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 7, 9019, 2509306671, 212180664326328751, 8389667096561737605103329223, 227328735342370296661661894900118524516359, 5846438367263951495694598571033398108516477233229168235359
Offset: 1

Views

Author

R. H. Hardin, May 31 2012

Keywords

Comments

Diagonal of A212943.

Examples

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

Crossrefs

Cf. A212943.

A212938 Number of n X 3 0..2 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 181, 9019, 331489, 10669771, 320396041, 9245913139, 260489615329, 7229878904251, 198760197641401, 5430623746397059, 147781972534146769, 4010919223287633931, 108669462396348197161, 2940820425317878781779
Offset: 1

Views

Author

R. H. Hardin, May 31 2012

Keywords

Comments

Column 3 of A212943.

Examples

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

Crossrefs

Cf. A212943.

Formula

Empirical: a(n) = 55*a(n-1) - 936*a(n-2) + 4860*a(n-3).
a(n) = 10^n - 2*18^n + 27^n. - Vaclav Kotesovec, May 31 2012
Empirical g.f.: x*(1 + 126*x) / ((1 - 10*x)*(1 - 18*x)*(1 - 27*x)). - Colin Barker, Jul 21 2018

A212939 Number of nX4 0..3 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 10311, 6470341, 2509306671, 801439905901, 232665778445031, 64146409058631061, 17171607076234160991, 4517476409302006541821, 1176061942859281821190551, 304219071898389511351734181
Offset: 1

Views

Author

R. H. Hardin May 31 2012

Keywords

Comments

Column 4 of A212943

Examples

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

Formula

Empirical: a(n) = 631*a(n-1) -144700*a(n-2) +15035200*a(n-3) -702208000*a(n-4) +11468800000*a(n-5).
Empirical: a(n) = 100^n-3*160^n+256^n-35^n+2*80^n. R. J. Mathar, Jun 27 2012

A212940 Number of nX5 0..4 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 1016501, 10058484751, 52311221188001, 212180664326328751, 764898125476357657001, 2592491557886605293297751, 8492622463881130571398876001, 27285563319283684654297283766751
Offset: 1

Views

Author

R. H. Hardin May 31 2012

Keywords

Comments

Column 5 of A212943

Examples

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

Formula

Empirical: a(n) = 8001*a(n-1) -24144750*a(n-2) +35582371250*a(n-3) -27539217890625*a(n-4) +11055908759765625*a(n-5) -2081011816406250000*a(n-6) +133539505004882812500*a(n-7).
Empirical: a(n) = -2*350^n+3*875^n+3*1125^n+3125^n+126^n-4*1875^n-2*525^n. R. J. Mathar, Jun 27 2012

A212941 Number of n X 6 0..5 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 152747323, 28744943858947, 2438624218076957695, 153322267564381742818531, 8389667096561737605103329223, 427593510370812774462812710051387, 20973117493971065058428815227499445215
Offset: 1

Views

Author

R. H. Hardin, May 31 2012

Keywords

Comments

Column 6 of A212943.

Examples

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

Crossrefs

Cf. A212943.

Formula

Empirical: a(n) = 130453*a(n-1) -6763333836*a(n-2) +185208872760324*a(n-3) -2991440828618168976*a(n-4) +29966228467174160130816*a(n-5) -189618846625740940674481152*a(n-6) +754213725094693350993932353536*a(n-7) -1831929539263722316502211827073024*a(n-8) +2545588680910314328406052486644760576*a(n-9) -1758206800538810904218951296840095498240*a(n-10) +418951577236630476027552063815969641857024*a(n-11).
Empirical: a(n) = 6*15876^n -3*4536^n +2*1512^n +3136^n -5*27216^n -462^n -6*7056^n -9261^n +4*12096^n +2*2646^n +46656^n. - R. J. Mathar, Jun 27 2012

A212942 Number of nX7 0..6 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 32383630189, 135992452878101359, 221920456466342315024785, 255478496068295791189905082231, 250841509251155966625680184691562929, 227328735342370296661661894900118524516359
Offset: 1

Views

Author

R. H. Hardin May 31 2012

Keywords

Comments

Column 7 of A212943

Examples

			Some solutions for n=4
..4..4..6..0..3..5..3....1..4..6..5..4..6..6....2..5..2..0..2..5..4
..3..4..5..1..5..0..5....2..3..4..3..4..6..0....5..1..4..6..5..5..3
..4..2..4..1..6..1..1....5..5..6..5..6..0..3....5..5..0..4..6..4..3
..6..6..0..3..2..1..1....6..2..0..3..3..5..5....1..3..1..1..3..5..3
		

Formula

Empirical: a(n) = 2323483*a(n-1) -2167154969952*a(n-2) +1086330796113513244*a(n-3) -329778884328286978977952*a(n-4) +64517502456132437770369148544*a(n-5) -8421554343462670052897532765935616*a(n-6) +747012180292693168982253383087616310272*a(n-7) -45320700037087646211097507312328132762984448*a(n-8) +1872991150391269654429084597380378344674028617728*a(n-9) -51936059702018704067955656273063090467733238547218432*a(n-10) +938955828089973458590692996057468119367652949010608553984*a(n-11) -10544878359956363252917775501846837273628118104421027150823424*a(n-12) +67581624519887879771651501946182123485150605725959917286635601920*a(n-13) -209181393867491964480827236276816398998810506947956308433062959513600*a(n-14) +205819420752306963772376008790571963882492713708055771807588273881088000*a(n-15)

A212944 Number of 2Xn 0..n-1 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 7, 181, 10311, 1016501, 152747323, 32383630189, 9192184928839, 3362887443335365, 1540205755192368507, 863047803911184565037, 580733337119861320815291, 462049013032247252827284109
Offset: 1

Views

Author

R. H. Hardin May 31 2012

Keywords

Comments

Row 2 of A212943

Examples

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

A212945 Number of 3Xn 0..n-1 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 37, 9019, 6470341, 10058484751, 28744943858947, 135992452878101359, 989783189762563737541, 10495013926448689085587447, 155433527883236057504375249287, 3109085470816411449764436167502547
Offset: 1

Views

Author

R. H. Hardin May 31 2012

Keywords

Comments

Row 3 of A212943

Examples

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

A212946 Number of 4Xn 0..n-1 arrays with no column j greater than or equal to than column j-1 in all rows.

Original entry on oeis.org

1, 175, 331489, 2509306671, 52311221188001, 2438624218076957695, 221920456466342315024785, 35805749325509532346413477679, 9531951779328890331855321215698177
Offset: 1

Views

Author

R. H. Hardin May 31 2012

Keywords

Comments

Row 4 of A212943

Examples

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