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 1-7 of 7 results.

A252821 Number of n X n nonnegative integer arrays with upper left 0 and every value within 3 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

1, 6, 81, 1920, 54376, 1679072, 55960651, 2001017650, 76084625352, 3047083917080, 127445868976818, 5528160760257164, 247294135503496534, 11357522219262644466, 533619846702969331737, 25573797311727396663076
Offset: 1

Views

Author

R. H. Hardin, Dec 22 2014

Keywords

Comments

Diagonal of A252828

Examples

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

A252822 Number of n X 2 nonnegative integer arrays with upper left 0 and every value within 3 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

2, 6, 18, 53, 142, 339, 729, 1437, 2638, 4568, 7536, 11937, 18266, 27133, 39279, 55593, 77130, 105130, 141038, 186525, 243510, 314183, 401029, 506853, 634806, 788412, 971596, 1188713, 1444578, 1744497, 2094299, 2500369, 2969682, 3509838, 4129098
Offset: 1

Views

Author

R. H. Hardin, Dec 22 2014

Keywords

Examples

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

Crossrefs

Column 2 of A252828.

Formula

Empirical: a(n) = (1/720)*n^6 + (7/240)*n^5 + (5/144)*n^4 - (11/48)*n^3 + (527/360)*n^2 - (3/10)*n + 1.
Conjectures from Colin Barker, Dec 06 2018: (Start)
G.f.: x*(2 - 8*x + 18*x^2 - 17*x^3 + 9*x^4 - 4*x^5 + x^6) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>7.
(End)

A252823 Number of n X 3 nonnegative integer arrays with upper left 0 and every value within 3 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

4, 18, 81, 340, 1238, 3891, 10761, 26764, 60988, 129236, 257653, 487744, 883142, 1538541, 2591269, 4236040, 6743492, 10483190, 15951849, 23807612, 34911302, 50375655, 71623633, 100457012, 139136540, 190475064, 257945133, 345802696
Offset: 1

Views

Author

R. H. Hardin, Dec 22 2014

Keywords

Examples

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

Crossrefs

Column 3 of A252828.

Formula

Empirical: a(n) = (1/90720)*n^9 + (1/2520)*n^8 + (19/3780)*n^7 + (1/45)*n^6 + (157/4320)*n^5 + (31/180)*n^4 + (28507/45360)*n^3 + (769/2520)*n^2 + (1783/630)*n.
Conjectures from Colin Barker, Dec 06 2018: (Start)
G.f.: x*(4 - 22*x + 81*x^2 - 140*x^3 + 163*x^4 - 137*x^5 + 75*x^6 - 23*x^7 + 3*x^8) / (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)

A252824 Number of n X 4 nonnegative integer arrays with upper left 0 and every value within 3 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

8, 53, 340, 1920, 9075, 36292, 125892, 387849, 1082111, 2777103, 6637625, 14922949, 31813809, 64737785, 126429330, 238046837, 433778614, 767506845, 1322268502, 2223460226, 3656986483, 5893853502, 9323072932, 14495166797, 22179067861
Offset: 1

Views

Author

R. H. Hardin, Dec 22 2014

Keywords

Comments

Column 4 of A252828.

Examples

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

Crossrefs

Cf. A252828.

Formula

Empirical: a(n) = (29/479001600)*n^12 + (29/8870400)*n^11 + (3083/43545600)*n^10 + (233/290304)*n^9 + (75539/14515200)*n^8 + (56551/2419200)*n^7 + (4051409/43545600)*n^6 + (123049/483840)*n^5 + (5473861/10886400)*n^4 + (1817149/1814400)*n^3 + (5653001/1663200)*n^2 + (23839/13860)*n + 1.

A252825 Number of nX5 nonnegative integer arrays with upper left 0 and every value within 3 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

15, 142, 1238, 9075, 54376, 271846, 1165921, 4396009, 14863460, 45791493, 130210765, 345350438, 861722537, 2037396931, 4591832266, 9915068062, 20600380173, 41336047432, 80360448168, 151781791285, 279198974102
Offset: 1

Views

Author

R. H. Hardin, Dec 22 2014

Keywords

Comments

Column 5 of A252828

Examples

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

Formula

Empirical: a(n) = (29/130767436800)*n^15 + (29/1743565824)*n^14 + (761/1437004800)*n^13 + (4567/479001600)*n^12 + (156803/1437004800)*n^11 + (467/537600)*n^10 + (4895111/914457600)*n^9 + (8221817/304819200)*n^8 + (969313/9331200)*n^7 + (3241009/10886400)*n^6 + (129913907/179625600)*n^5 + (29795933/19958400)*n^4 + (1495061807/454053600)*n^3 + (185734933/50450400)*n^2 + (148987/27720)*n

A252826 Number of nX6 nonnegative integer arrays with upper left 0 and every value within 3 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

26, 339, 3891, 36292, 271846, 1679072, 8807722, 40232545, 163307844, 598768118, 2009666884, 6242686351, 18111918515, 49456857086, 127928520595, 315195592486, 743219906659, 1684034391078, 3679765581966, 7778027858175, 15947032415637
Offset: 1

Views

Author

R. H. Hardin, Dec 22 2014

Keywords

Comments

Column 6 of A252828

Examples

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

Formula

Empirical: a(n) = (883/1600593426432000)*n^18 + (883/16167610368000)*n^17 + (148963/62768369664000)*n^16 + (6599/108972864000)*n^15 + (8020459/7846046208000)*n^14 + (3062099/249080832000)*n^13 + (813736283/7242504192000)*n^12 + (166116079/201180672000)*n^11 + (1097726573/219469824000)*n^10 + (598115773/24385536000)*n^9 + (466445792503/4828336128000)*n^8 + (272090281/870912000)*n^7 + (19554578278049/23538138624000)*n^6 + (1173600978721/653837184000)*n^5 + (4602055984369/1307674368000)*n^4 + (98334957191/18162144000)*n^3 + (263932729939/30875644800)*n^2 + (3637273/816816)*n + 1

A252827 Number of n X 7 nonnegative integer arrays with upper left 0 and every value within 3 of its city block distance from the upper left and every value increasing by 0 or 1 with every step right or down.

Original entry on oeis.org

42, 729, 10761, 125892, 1165921, 8807722, 55960651, 306796310, 1481748658, 6411737114, 25203579317, 91037124979, 305083525901, 956286103952, 2823092600299, 7895877354183, 21029532417878, 53571661955209
Offset: 1

Views

Author

R. H. Hardin, Dec 22 2014

Keywords

Comments

Column 7 of A252828.

Examples

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

Crossrefs

Cf. A252828.

Formula

Empirical: a(n) = (491/510909421717094400)*n^21 + (491/4054836680294400)*n^20 + (31237/4561691265331200)*n^19 + (16931/72754246656000)*n^18 + (6860417/1280474741145600)*n^17 + (5620079/62768369664000)*n^16 + (28238557/24715045555200)*n^15 + (460207/39626496000)*n^14 + (1996189759/20542375526400)*n^13 + (9849852413/14485008384000)*n^12 + (262128023/65840947200)*n^11 + (23507656471/1207084032000)*n^10 + (126607207245823/1581762915532800)*n^9 + (1573022155907/5706215424000)*n^8 + (887749472755/1129830653952)*n^7 + (43972723546711/23538138624000)*n^6 + (101853364790929/26676557107200)*n^5 + (13152985155929/2020951296000)*n^4 + (11601438763393/1119943843200)*n^3 + (5765297083043/586637251200)*n^2 + (131188073/15519504)*n.
Showing 1-7 of 7 results.