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.

A200987 Number of nX5 0..4 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

1, 21, 140, 1095, 4919, 27000, 97341, 383172, 1188521, 3704820, 9947816, 27240277, 65292069, 157646021, 349738426, 770969390, 1585648871, 3256248216, 6303135880, 12177430692, 22459794938, 41128002746, 72582886199, 127586136583
Offset: 1

Views

Author

R. H. Hardin Nov 25 2011

Keywords

Comments

Column 5 of A200990

Examples

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

Links

A200984 Number of nX2 0..4 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

10, 10, 20, 79, 21, 226, 157, 227, 678, 120, 1272, 789, 1015, 2697, 404, 4232, 2484, 3008, 7496, 1025, 10650, 6050, 7060, 16895, 2181, 22530, 12525, 14255, 33174, 4116, 42336, 23177, 25907, 59073, 7120, 72992, 39504, 43560, 97792, 11529, 117882, 63234
Offset: 1

Views

Author

R. H. Hardin Nov 25 2011

Keywords

Comments

Column 2 of A200990

Examples

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

Links

Formula

Empirical: a(n) = 5*a(n-5) -10*a(n-10) +10*a(n-15) -5*a(n-20) +a(n-25)
Subsequences for n modulo 5 = 1,2,3,4,0:
p=(n+4)/5: a(n) = (115/6)*p^4 - 11*p^3 + (11/6)*p^2
q=(n+3)/5: a(n) = (115/12)*q^4 + (1/2)*q^3 - (1/12)*q^2
r=(n+2)/5: a(n) = (115/12)*r^4 + (49/6)*r^3 + (23/12)*r^2 + (1/3)*r
s=(n+1)/5: a(n) = (115/6)*s^4 + 35*s^3 + (125/6)*s^2 + 4*s
t=(n+0)/5: a(n) = (23/12)*t^4 + (37/6)*t^3 + (91/12)*t^2 + (13/3)*t + 1

A200985 Number of nX3 0..4 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

10, 20, 92, 537, 140, 3157, 3604, 6692, 26168, 5408, 84188, 69613, 118244, 371475, 57479, 864418, 645309, 916025, 2639447, 387005, 5166751, 3514237, 4833175, 12896465, 1709869, 22408038, 14621090, 18653741, 47941297, 6213321, 76880715
Offset: 1

Views

Author

R. H. Hardin Nov 25 2011

Keywords

Comments

Column 3 of A200990

Examples

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

Links

A200986 Number of n X 4 0..4 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

5, 79, 537, 1225, 1095, 15023, 95845, 268375, 325061, 168262, 1743684, 7499861, 15130265, 14517651, 5800482, 49981930, 178151444, 307672792, 257468817, 87287958, 681245186, 2178690191, 3396865595, 2581813804, 796596745
Offset: 1

Views

Author

R. H. Hardin, Nov 25 2011

Keywords

Comments

Column 4 of A200990.

Examples

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

Links

Crossrefs

Cf. A200990.

A200988 Number of nX6 0..4 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

5, 226, 3157, 15023, 27000, 752271, 8434277, 39361323, 80878071, 64001290, 1061617971, 6885026630, 20690808333, 29111264965, 15934951732, 200246707818, 986856290325, 2324162438865, 2632647531203, 1170193845706, 12359035000524
Offset: 1

Views

Author

R. H. Hardin Nov 25 2011

Keywords

Comments

Column 6 of A200990

Examples

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

Links

A200983 Number of n X n 0..4 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

5, 10, 92, 1225, 4919, 752271, 29555346, 1278883650, 65182166083, 731587297275
Offset: 1

Views

Author

R. H. Hardin Nov 25 2011

Keywords

Comments

Diagonal of A200990

Examples

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

A200989 Number of nX7 0..4 arrays with every row and column nondecreasing rightwards and downwards, and the number of instances of each value within one of each other.

Original entry on oeis.org

10, 157, 3604, 95845, 97341, 8434277, 29555346, 171588826, 1801771085, 853004113, 35516752065, 68635361025, 249178222379, 1665476375295, 526294467301, 15773537280426, 22528310745889
Offset: 1

Views

Author

R. H. Hardin Nov 25 2011

Keywords

Comments

Column 7 of A200990

Examples

			Some solutions for n=3
..0..0..0..0..2..2..4....0..0..0..2..2..2..4....0..0..1..1..2..3..3
..0..1..1..2..3..3..4....0..1..1..2..2..3..4....0..1..1..1..3..4..4
..1..1..2..3..3..4..4....1..1..3..3..3..4..4....0..2..2..2..3..4..4
Showing 1-7 of 7 results.

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