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 1-9 of 9 results.

A252876 T(n,k) = Number of n X k nonnegative integer arrays with upper left 0 and lower right n+k-4 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

0, 0, 0, 1, 1, 1, 3, 8, 8, 3, 6, 26, 44, 26, 6, 10, 61, 153, 153, 61, 10, 15, 120, 413, 615, 413, 120, 15, 21, 211, 949, 1953, 1953, 949, 211, 21, 28, 343, 1948, 5281, 7313, 5281, 1948, 343, 28, 36, 526, 3676, 12686, 23203, 23203, 12686, 3676, 526, 36, 45, 771, 6497, 27805, 64920, 85801, 64920, 27805, 6497, 771, 45
Offset: 1

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Author

R. H. Hardin, Dec 24 2014

Keywords

Comments

Table starts
..0...0.....1......3......6......10.......15........21........28.........36
..0...1.....8.....26.....61.....120......211.......343.......526........771
..1...8....44....153....413.....949.....1948......3676......6497......10894
..3..26...153....615...1953....5281....12686.....27805.....56624.....108549
..6..61...413...1953...7313...23203....64920....164399....383735.....836797
.10.120...949...5281..23203...85801...277585....806347...2142634....5281314
.15.211..1948..12686..64920..277585..1030330...3407823..10237249...28340232
.21.343..3676..27805.164399..806347..3407823..12742873..42993671..132872804
.28.526..6497..56624.383735.2142634.10237249..42993671.161937617..555632319
.36.771.10894.108549.836797.5281314.28340232.132872804.555632319.2105918045

Examples

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

Crossrefs

Columns 1-7 give: A000217(n-2), A252870, A252871, A252872, A252873, A252874, A252875.
Main diagonal is A252869.

Formula

Empirical for column k:
k=1: a(n) = (1/2)*n^2 - (3/2)*n + 1
k=2: a(n) = (1/24)*n^4 + (5/12)*n^3 - (13/24)*n^2 - (11/12)*n + 1,
k=3: [polynomial of degree 6]
k=4: [polynomial of degree 8]
k=5: [polynomial of degree 10]
k=6: [polynomial of degree 12]
k=7: [polynomial of degree 14]
Empirical: with "n+k-3" instead of "n+k-4" T(n,k) = binomial(n+k,k) - 2.

A252976 T(n,k) = Number of n X k nonnegative integer arrays with upper left 0 and lower right n+k-5 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 4, 13, 18, 13, 4, 10, 61, 153, 153, 61, 10, 20, 192, 770, 1236, 770, 192, 20, 35, 483, 2859, 6997, 6997, 2859, 483, 35, 56, 1050, 8694, 30802, 46812, 30802, 8694, 1050, 56, 84, 2058, 22924, 112877, 248182, 248182, 112877, 22924, 2058
Offset: 1

Views

Author

R. H. Hardin, Dec 25 2014

Keywords

Comments

Table starts
..0....0......0.......1........4........10.........20..........35...........56
..0....0......1......13.......61.......192........483........1050.........2058
..0....1.....18.....153......770......2859.......8694.......22924........54272
..1...13....153....1236.....6997.....30802.....112877......359550......1024773
..4...61....770....6997....46812....248182....1100210.....4230324.....14477724
.10..192...2859...30802...248182...1592348....8528422....39423196....161160206
.20..483...8694..112877..1100210...8528422...54926890...303382053...1471499970
.35.1050..22924..359550..4230324..39423196..303382053..1988261908..11360377192
.56.2058..54272.1024773.14477724.161160206.1471499970.11360377192..75922639116
.84.3732.118057.2667554.44951694.593478797.6383377435.57644900961.447545856560

Examples

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

Crossrefs

Cf. A252876, A252930. Column 1 is A000292(n-3). Cf. A252970-A252975 (columns 2-7).

Formula

Empirical for column k:
k=1: a(n) = (1/6)*n^3 - 1*n^2 + (11/6)*n - 1
k=2: [polynomial of degree 6]
k=3: [polynomial of degree 9]
k=4: [polynomial of degree 12]
k=5: [polynomial of degree 15]
k=6: [polynomial of degree 18]
k=7: [polynomial of degree 21]
Empirical: with "n+k-3" instead of "n+k-5" T(n,k) = binomial(n+k,k) - 2, see A166810, A166812, A166813.

A252923 Number of n X n nonnegative integer arrays with upper left 0 and lower right n+n-6 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

0, 0, 1, 615, 84910, 8241540, 759337545, 73117894428, 7578889491370, 848729993032718, 102072779621746876, 13069744040275286234, 1766655687081261435255, 250232365919081938956865, 36910187948533534644694094
Offset: 1

Views

Author

R. H. Hardin, Dec 24 2014

Keywords

Examples

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

Crossrefs

Diagonal of A252930.

A252924 Number of n X 2 nonnegative integer arrays with upper left 0 and lower right n+2-6 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

0, 0, 0, 1, 19, 120, 483, 1500, 3923, 9069, 19095, 37356, 68860, 120835, 203424, 330525, 520794, 798830, 1196562, 1754859, 2525385, 3572722, 4976785, 6835554, 9268149, 12418275, 16458065, 21592350, 28063386, 36156069, 46203670, 58594123
Offset: 1

Views

Author

R. H. Hardin, Dec 24 2014

Keywords

Comments

Column 2 of A252930.

Examples

			Some solutions for n=6:
..0..0....0..0....0..1....0..0....0..0....0..1....0..0....0..0....0..1....0..0
..0..1....1..1....1..1....1..1....0..0....0..1....0..1....0..0....0..1....1..1
..1..1....1..1....1..1....2..2....1..1....0..1....0..1....0..1....0..1....1..1
..1..1....1..1....1..2....2..2....1..1....0..1....1..1....1..1....0..1....1..2
..1..2....1..1....2..2....2..2....1..2....0..1....1..1....1..1....1..1....2..2
..2..2....1..2....2..2....2..2....1..2....1..2....2..2....1..2....1..2....2..2
		

Formula

Empirical: a(n) = (1/40320)*n^8 + (1/1120)*n^7 + (7/2880)*n^6 - (1/16)*n^5 + (647/5760)*n^4 + (87/160)*n^3 - (21317/10080)*n^2 + (141/56)*n - 1.
Empirical: G.f.: x^4*(-1-10*x+15*x^2-3*x^3-3*x^4+x^5) / (x-1)^9 . - R. J. Mathar, Nov 21 2015

A252929 Number of nX7 nonnegative integer arrays with upper left 0 and lower right n+7-6 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

15, 483, 13976, 315198, 5385305, 71297441, 759337545, 6725497344, 50869309436, 335549742230, 1963313662947, 10332594393296, 49485574097413, 217813226273441, 888570804281664, 3384240524056852, 12109669540486657
Offset: 1

Views

Author

R. H. Hardin, Dec 24 2014

Keywords

Comments

Column 7 of A252930

Examples

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

Formula

Empirical polynomial of degree 28 (see link above)

A252925 Number of n X 3 nonnegative integer arrays with upper left 0 and lower right n+3-6 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

0, 0, 1, 33, 413, 2859, 13976, 54199, 177848, 513905, 1342933, 3233784, 7275049, 15451358, 31234528, 60485192, 112793064, 203424686, 356097793, 606862907, 1009447181, 1642504781, 2619324320, 4100669333, 6311574992, 9563095895
Offset: 1

Views

Author

R. H. Hardin, Dec 24 2014

Keywords

Comments

Column 3 of A252930.

Examples

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

Formula

Empirical: a(n) = (1/59875200)*n^12 + (1/997920)*n^11 + (31/1360800)*n^10 + (1/5040)*n^9 + (79/453600)*n^8 - (71/15120)*n^7 - (4127/1360800)*n^6 + (319/9072)*n^5 + (52061/5443200)*n^4 - (2587/6048)*n^3 + (3315209/1663200)*n^2 - (11097/3080)*n + 2.
Empirical: G.f.: -x^3*(1 +20*x +62*x^2 -222*x^3 +300*x^4 -297*x^5 +255*x^6 -167*x^7 +72*x^8 -18*x^9 +2*x^10) / (x-1)^13. - R. J. Mathar, Nov 21 2015

A252926 Number of n X 4 nonnegative integer arrays with upper left 0 and lower right n+4-6 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

0, 1, 33, 615, 6997, 53950, 315198, 1499394, 6083808, 21733215, 69921908, 206052448, 563440284, 1444285973, 3499040581, 8065603025, 17787652381, 37705694442, 77126966988, 152747362302, 293741640632, 549886035657
Offset: 1

Views

Author

R. H. Hardin, Dec 24 2014

Keywords

Comments

Column 4 of A252930.

Examples

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

Crossrefs

Cf. A252930.

Formula

Empirical: a(n) = (13/1609445376000)*n^16 + (13/18289152000)*n^15 + (3947/149448499200)*n^14 + (20057/37362124800)*n^13 + (728009/114960384000)*n^12 + (312437/7185024000)*n^11 + (1303193/7315660800)*n^10 + (848039/1828915200)*n^9 + (11500417/20901888000)*n^8 - (1346209/373248000)*n^7 - (14478857/1149603840)*n^6 - (361673/8164800)*n^5 + (13716552599/33530112000)*n^4 + (454863863/1397088000)*n^3 - (207327073/86486400)*n^2 + (137883/80080)*n.
Empirical: G.f.: x^2*(-1 -16*x -190*x^2 -350*x^3 +1419*x^4 -3792*x^5 +7860*x^6 -11238*x^7 +11247*x^8 -8133*x^9 +4280*x^10 -1600*x^11 +401*x^12 -60*x^13+4*x^14) / (x-1)^17. - R. J. Mathar, Nov 23 2015

A252927 Number of nX5 nonnegative integer arrays with upper left 0 and lower right n+5-6 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

1, 19, 413, 6997, 84910, 762227, 5385305, 31454256, 157376166, 692347393, 2731553014, 9814551889, 32510650689, 100275435009, 290361386801, 794754882094, 2068183070502, 5142171510385, 12267196687798, 28182388823719
Offset: 1

Views

Author

R. H. Hardin, Dec 24 2014

Keywords

Comments

Column 5 of A252930

Examples

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

Formula

Empirical: a(n) = (47/17888985354240000)*n^20 + (47/149074877952000)*n^19 + (167/10003708915200)*n^18 + (4591/8892185702400)*n^17 + (29063/2802159360000)*n^16 + (187361/1307674368000)*n^15 + (13481939/9415255449600)*n^14 + (1082533/98075577600)*n^13 + (454942751/6584094720000)*n^12 + (23035147/67060224000)*n^11 + (43650403/34488115200)*n^10 + (134989213/40236134400)*n^9 + (2353290548929/470762772480000)*n^8 - (1781952749/3923023104000)*n^7 + (174219179149/2353813862400)*n^6 + (1662462491/16345929600)*n^5 + (42818968289/66718080000)*n^4 - (16827599/22422400)*n^3 + (9481442611/5333065920)*n^2 - (565043267/116396280)*n + 4.
Empirical: G.f.: -x*(1 -2*x +224*x^2 +984*x^3 +5418*x^4 -7437*x^5 +43066*x^6 -112135*x^7 +198529*x^8 -285030*x^9 +339839*x^10 -332484*x^11 +266120*x^12 -174781*x^13 +93817*x^14 -40498*x^15 +13679*x^16 -3477*x^17 +627*x^18 -72*x^19 +4*x^20) / (x-1)^21 . - R. J. Mathar, Nov 24 2015

A252928 Number of nX6 nonnegative integer arrays with upper left 0 and lower right n+6-6 and value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

5, 120, 2859, 53950, 762227, 8241540, 71297441, 512868867, 3160111147, 17063990547, 82211677028, 358529577294, 1432148475494, 5291678799968, 18236349617760, 59031011794076, 180569195179185, 524679580969208
Offset: 1

Views

Author

R. H. Hardin, Dec 24 2014

Keywords

Comments

Column 6 of A252930

Examples

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

Formula

Empirical: a(n) = (331/583128197117706240000)*n^24 + (331/3738001263575040000)*n^23 + (31687/5070679974936576000)*n^22 + (9719/36584992604160000)*n^21 + (83457079/10948059036794880000)*n^20 + (2293999511/14597412049059840000)*n^19 + (70133801/28810681675776000)*n^18 + (11352513167/384142422343680000)*n^17 + (39752887/135444234240000)*n^16 + (18525490537/7532204359680000)*n^15 + (1041895258531/59655058528665600)*n^14 + (51595236448757/497125487738880000)*n^13 + (383722831905761/745688231608320000)*n^12 + (7387354289669/3476402012160000)*n^11 + (96126694933271/13557967847424000)*n^10 + (3074811780539/156920924160000)*n^9 + (7254553057678669/144053408378880000)*n^8 + (5122046760654749/48017802792960000)*n^7 + (615467828621/1796401152000)*n^6 + (481180027609747/666913927680000)*n^5 + (6796574742313/5225109120000)*n^4 + (10424925937303/10188962784000)*n^3 - (3393867242681/1060137318240)*n^2 + (7032359801/2677114440)*n + 2
Showing 1-9 of 9 results.