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 12 results. Next

A229439 Number of n X 2 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

4, 7, 13, 25, 47, 84, 142, 228, 350, 517, 739, 1027, 1393, 1850, 2412, 3094, 3912, 4883, 6025, 7357, 8899, 10672, 12698, 15000, 17602, 20529, 23807, 27463, 31525, 36022, 40984, 46442, 52428, 58975, 66117, 73889, 82327, 91468, 101350, 112012, 123494
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Examples

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

Crossrefs

Column 2 of A229445.

Formula

Empirical: a(n) = (1/24)*n^4 + (1/12)*n^3 - (1/24)*n^2 + (23/12)*n + 2.
Conjectures from Colin Barker, Sep 16 2018: (Start)
G.f.: x*(4 - 13*x + 18*x^2 - 10*x^3 + 2*x^4) / (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)

A229440 Number of n X 3 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

5, 10, 22, 53, 128, 293, 625, 1244, 2327, 4124, 6976, 11335, 17786, 27071, 40115, 58054, 82265, 114398, 156410, 210601, 279652, 366665, 475205, 609344, 773707, 973520, 1214660, 1503707, 1847998, 2255683, 2735783, 3298250, 3954029, 4715122
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Examples

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

Crossrefs

Column 3 of A229445.

Formula

Empirical: a(n) = (1/360)*n^6 + (1/120)*n^5 + (1/36)*n^4 + (5/24)*n^3 - (11/360)*n^2 + (167/60)*n + 2.
Conjectures from Colin Barker, Sep 17 2018: (Start)
G.f.: x*(5 - 25*x + 57*x^2 - 66*x^3 + 44*x^4 - 15*x^5 + 2*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)

A229441 Number of n X 4 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

6, 14, 37, 109, 324, 915, 2402, 5843, 13229, 28071, 56234, 107080, 194989, 341334, 576993, 945488, 1506848, 2342300, 3559899, 5301215, 7749202, 11137381, 15760476, 21986649, 30271487, 41173901, 55374104, 73693842, 97119059, 126825184
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Examples

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

Crossrefs

Column 4 of A229445.

Formula

Empirical: a(n) = (1/5760)*n^8 + (1/2016)*n^7 + (1/576)*n^6 + (11/360)*n^5 + (409/5760)*n^4 + (49/288)*n^3 + (41/96)*n^2 + (2771/840)*n + 2.
Conjectures from Colin Barker, Sep 17 2018: (Start)
G.f.: x*(6 - 40*x + 127*x^2 - 224*x^3 + 255*x^4 - 177*x^5 + 77*x^6 - 19*x^7 + 2*x^8) / (1 - x)^9.
a(n) = 9*a(n-1) - 36*a(n-2) + 84*a(n-3) - 126*a(n-4) + 126*a(n-5) - 84*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9) for n>9.
(End)

A229442 Number of n X 5 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

7, 19, 60, 212, 753, 2546, 8024, 23428, 63430, 159945, 377840, 841419, 1777036, 3578998, 6908102, 12834739, 23041529, 40103959, 67871516, 111976374, 180501843, 284848554, 440842772, 670138334, 1001971536, 1475336877, 2141660944
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Examples

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

Crossrefs

Column 5 of A229445.

Formula

Empirical: a(n) = (1/103680)*n^10 + (1/80640)*n^9 + (1/12096)*n^8 + (47/13440)*n^7 + (11/6912)*n^6 + (173/3840)*n^5 + (1187/10368)*n^4 + (12437/20160)*n^3 - (6211/10080)*n^2 + (4901/840)*n + 1.
Conjectures from Colin Barker, Sep 17 2018: (Start)
G.f.: x*(7 - 58*x + 236*x^2 - 558*x^3 + 896*x^4 - 941*x^5 + 709*x^6 - 343*x^7 + 103*x^8 - 17*x^9 + x^10) / (1 - x)^11.
a(n) = 11*a(n-1) - 55*a(n-2) + 165*a(n-3) - 330*a(n-4) + 462*a(n-5) - 462*a(n-6) + 330*a(n-7) - 165*a(n-8) + 55*a(n-9) - 11*a(n-10) + a(n-11) for n>11.
(End)

A229443 Number of nX6 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

8, 25, 93, 387, 1609, 6374, 23610, 81177, 258698, 765702, 2113491, 5467941, 13331626, 30795942, 67738085, 142526854, 288060848, 561310955, 1057997269, 1934623043, 3440842683, 5966088386, 10105555904, 16752093179, 27222289586
Offset: 1

Views

Author

R. H. Hardin Sep 23 2013

Keywords

Comments

Column 6 of A229445

Examples

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

Formula

Empirical: a(n) = (73/159667200)*n^12 - (19/26611200)*n^11 + (19/2903040)*n^10 + (47/161280)*n^9 - (1259/1612800)*n^8 + (7711/806400)*n^7 - (10715/580608)*n^6 + (30575/96768)*n^5 - (4597853/3628800)*n^4 + (1198483/201600)*n^3 - (621689/55440)*n^2 + (168439/9240)*n - 4

A229444 Number of n X 7 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

9, 32, 138, 665, 3184, 14536, 62205, 247607, 914271, 3133068, 9990129, 29755249, 83162347, 219151523, 547116607, 1299869098, 2951439969, 6429248828, 13483439736, 27310437901, 53577074678, 102061137870, 189220453845
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Comments

Column 7 of A229445.

Examples

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

Crossrefs

Cf. A229445.

Formula

Empirical: a(n) = (797/43589145600)*n^14 - (127/1245404160)*n^13 + (1/1451520)*n^12 + (335/19160064)*n^11 - (1381/10886400)*n^10 + (449/322560)*n^9 - (216523/30481920)*n^8 + (653459/8709120)*n^7 - (2384537/4838400)*n^6 + (2642473/870912)*n^5 - (275452937/23950080)*n^4 + (131909609/3991680)*n^3 - (38524939/687960)*n^2 + (21925483/360360)*n - 20.

A229446 Number of 3 X n 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

8, 13, 22, 37, 60, 93, 138, 197, 272, 365, 478, 613, 772, 957, 1170, 1413, 1688, 1997, 2342, 2725, 3148, 3613, 4122, 4677, 5280, 5933, 6638, 7397, 8212, 9085, 10018, 11013, 12072, 13197, 14390, 15653, 16988, 18397, 19882, 21445, 23088, 24813, 26622, 28517
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Examples

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

Crossrefs

Row 3 of A229445.

Formula

Empirical: a(n) = (1/3)*n^3 + (8/3)*n + 5.
Conjectures from Colin Barker, Sep 17 2018: (Start)
G.f.: x*(8 - 19*x + 18*x^2 - 5*x^3) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>4.
(End)

A229447 Number of 4 X n 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

12, 25, 53, 109, 212, 387, 665, 1083, 1684, 2517, 3637, 5105, 6988, 9359, 12297, 15887, 20220, 25393, 31509, 38677, 47012, 56635, 67673, 80259, 94532, 110637, 128725, 148953, 171484, 196487, 224137, 254615, 288108, 324809, 364917, 408637, 456180
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Examples

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

Crossrefs

Row 4 of A229445.

Formula

Empirical: a(n) = (1/4)*n^4 - (1/3)*n^3 + (13/4)*n^2 + (11/6)*n + 7.
Conjectures from Colin Barker, Sep 17 2018: (Start)
G.f.: x*(12 - 35*x + 48*x^2 - 26*x^3 + 7*x^4) / (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)

A229448 Number of 5 X n 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

17, 47, 128, 324, 753, 1609, 3184, 5890, 10281, 17075, 27176, 41696, 61977, 89613, 126472, 174718, 236833, 315639, 414320, 536444, 685985, 867345, 1085376, 1345402, 1653241, 2015227, 2438232, 2929688, 3497609, 4150613, 4897944, 5749494, 6715825
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Examples

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

Crossrefs

Row 5 of A229445.

Formula

Empirical: a(n) = (11/60)*n^5 - (1/2)*n^4 + (15/4)*n^3 - 1*n^2 + (257/30)*n + 6.
Conjectures from Colin Barker, Sep 17 2018: (Start)
G.f.: x*(17 - 55*x + 101*x^2 - 79*x^3 + 44*x^4 - 6*x^5) / (1 - x)^6.
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
(End)

A229449 Number of 6 X n 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.

Original entry on oeis.org

23, 84, 293, 915, 2546, 6374, 14536, 30571, 59969, 110816, 194535, 326723, 528084, 825458, 1252946, 1853131, 2678395, 3792332, 5271257, 7205811, 9702662, 12886302, 16900940, 21912491, 28110661, 35711128, 44957819, 56125283, 69521160, 85488746
Offset: 1

Views

Author

R. H. Hardin, Sep 23 2013

Keywords

Examples

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

Crossrefs

Row 6 of A229445.

Formula

Empirical: a(n) = (2/15)*n^6 - (5/8)*n^5 + (9/2)*n^4 - (55/8)*n^3 + (283/15)*n^2 - 4*n + 11.
Conjectures from Colin Barker, Sep 17 2018: (Start)
G.f.: x*(23 - 77*x + 188*x^2 - 177*x^3 + 159*x^4 - 31*x^5 + 11*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)
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