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 11 results. Next

A267464 Number of length-n 0..n arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

2, 9, 58, 515, 5921, 83972, 1418740, 27838701, 622347697, 15615978774, 434592601906, 13284763035843, 442468160695185, 15948347001674856, 618492693332510536, 25678060436644303705, 1136319246969590031009
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Diagonal of A267471.

Examples

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

Crossrefs

Cf. A267471.

A267465 Number of length-n 0..2 arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

3, 9, 24, 62, 160, 418, 1112, 3018, 8352, 23522, 67240, 194554, 568304, 1672146, 4946808, 14692970, 43767616, 130647490, 390566216, 1168815066, 3500415888, 10488664754, 31439779864, 94264813642, 282681194720, 847808703138
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Column 2 of A267471.

Examples

			Some solutions for n=7:
..2....1....2....1....2....2....1....1....1....0....1....0....0....1....1....2
..1....0....1....0....1....2....2....0....1....1....2....1....1....2....2....2
..0....2....0....1....0....2....0....1....0....0....2....1....2....2....1....1
..1....2....1....0....1....0....1....2....1....1....1....0....1....2....0....1
..2....2....2....2....1....1....0....2....1....0....0....0....0....1....1....2
..2....0....1....0....0....0....2....1....1....1....0....0....1....2....2....2
..1....2....2....1....0....1....0....1....1....0....1....0....1....0....2....2
		

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = 8*a(n-1) -23*a(n-2) +28*a(n-3) -12*a(n-4).
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: x*(3 - 15*x + 21*x^2 - 7*x^3) / ((1 - x)*(1 - 2*x)^2*(1 - 3*x)).
a(n) = 2^n + 3^(n-1) + 2^(n-2)*(n+1) - 1.
(End)

A267466 Number of length-n 0..3 arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

4, 16, 58, 204, 712, 2490, 8770, 31200, 112300, 409254, 1510102, 5638956, 21290368, 81183858, 312262954, 1210023672, 4718194516, 18492663102, 72787129726, 287468548548, 1138446338344, 4518338475786, 17963524388818, 71514144464784
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Column 3 of A267471.

Examples

			Some solutions for n=7:
..0....1....1....0....3....3....3....1....2....0....1....0....1....3....2....3
..3....3....0....3....3....1....3....2....3....2....0....3....3....3....0....3
..1....3....1....0....0....3....1....3....0....3....1....1....3....3....3....3
..0....0....1....3....3....3....0....3....3....3....3....0....1....2....3....3
..3....1....0....2....2....1....0....0....2....3....0....1....0....0....3....3
..2....0....0....3....2....3....3....0....2....0....3....1....2....0....3....2
..0....1....1....0....0....1....2....1....2....2....3....0....0....3....2....0
		

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = 13*a(n-1) -65*a(n-2) +155*a(n-3) -174*a(n-4) +72*a(n-5).
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: 2*x*(2 - 18*x + 55*x^2 - 65*x^3 + 23*x^4) / ((1 - x)*(1 - 2*x)*(1 - 3*x)^2*(1 - 4*x)).
a(n) = (-18 - 9*2^(1+n) + 50*3^n + 9*4^n + 4*3^n*n) / 36.
(End)

A267467 Number of length-n 0..4 arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

5, 25, 115, 515, 2285, 10119, 44901, 200119, 897301, 4052183, 18444197, 84651063, 391805877, 1828676887, 8604122053, 40793238647, 194778656213, 936040595031, 4524410973669, 21981448319671, 107275320299509, 525571712299415
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Column 4 of A267471.

Examples

			Some solutions for n=7:
..1....3....1....4....1....2....4....4....3....1....2....1....1....3....4....3
..4....4....4....1....3....1....4....0....3....0....3....4....2....1....1....1
..4....3....0....3....1....3....0....3....1....2....1....2....3....0....3....4
..1....4....1....3....3....0....0....1....2....4....3....1....1....4....3....3
..4....2....3....1....4....1....2....4....1....2....4....2....0....4....0....1
..1....1....2....2....4....2....2....2....2....3....1....0....4....4....0....0
..0....2....4....2....3....0....3....0....0....0....3....1....2....3....1....4
		

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = 19*a(n-1) -145*a(n-2) +565*a(n-3) -1174*a(n-4) +1216*a(n-5) -480*a(n-6).
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: x*(5 - 70*x + 365*x^2 - 870*x^3 + 920*x^4 - 326*x^5) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)^2*(1 - 5*x)).
a(n) = (-80 - 15*2^(2+n) - 80*3^n + 335*4^n + 48*5^n) / 240 + 4^(-2+n)*n.
(End)

A267468 Number of length-n 0..5 arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

6, 36, 201, 1096, 5921, 31880, 171601, 925176, 5002641, 27155800, 148092161, 811801256, 4475004961, 24813260520, 138416411121, 776822970136, 4385905536881, 24907563562040, 142244725848481, 816667390335816
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Column 5 of A267471.

Examples

			Some solutions for n=7:
..2....1....0....4....3....5....2....0....3....3....4....4....0....4....1....3
..0....3....3....1....1....0....0....4....0....3....3....3....3....4....4....1
..4....2....4....2....2....1....4....1....3....1....0....5....1....0....5....2
..0....4....1....3....0....5....0....5....0....0....3....1....2....0....2....1
..3....0....5....2....4....4....2....0....3....0....2....0....5....3....0....4
..4....2....3....2....4....1....5....4....2....3....0....1....5....2....4....3
..0....4....0....1....0....3....2....3....1....2....3....0....4....1....4....5
		

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = 26*a(n-1) -280*a(n-2) +1610*a(n-3) -5299*a(n-4) +9884*a(n-5) -9540*a(n-6) +3600*a(n-7).
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: x*(6 - 120*x + 945*x^2 - 3710*x^3 + 7539*x^4 - 7336*x^5 + 2556*x^6) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)^2*(1 - 6*x)).
a(n) = (-75 - 25*2^(1+n) - 50*3^n + 25*2^(1+n)*3^n - 75*4^n + 413*5^n + 12*5^n*n) / 300.
(End)

A267469 Number of length-n 0..6 arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

7, 49, 322, 2072, 13216, 83972, 532840, 3381860, 21491464, 136856180, 873803848, 5596638788, 35973158152, 232118471828, 1503949949896, 9786663686756, 63969334316680, 420026972347316, 2770499256109384, 18356852895660164
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Column 6 of A267471.

Examples

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

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = 34*a(n-1) -490*a(n-2) +3892*a(n-3) -18529*a(n-4) +53746*a(n-5) -91860*a(n-6) +83448*a(n-7) -30240*a(n-8).
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: x*(7 - 189*x + 2086*x^2 - 12110*x^3 + 39543*x^4 - 71617*x^5 + 65212*x^6 - 22212*x^7) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 6*x)^2*(1 - 7*x)).
a(n) = (-504 - 315*2^n - 280*3^n - 315*4^n - 504*5^n + 3409*6^n + 360*7^n + 35*2^(1+n)*3^n*n) / 2520.
(End)

A267470 Number of length-n 0..7 arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

8, 64, 484, 3592, 26440, 193852, 1418740, 10378144, 75944464, 556295860, 4080955516, 29994246136, 220942982968, 1631599880428, 12082194095812, 89736369169168, 668588308469152, 4997804102441956, 37486765952804428
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Column 7 of A267471.

Examples

			Some solutions for n=6:
..1....4....2....2....4....2....6....4....6....6....6....0....6....2....2....2
..0....7....6....5....6....7....3....6....3....0....7....2....3....5....0....7
..6....0....0....0....1....7....1....3....2....4....3....7....1....0....3....5
..1....3....0....1....4....5....5....6....1....3....2....7....7....7....7....0
..2....6....0....0....1....5....1....3....2....6....7....7....5....3....2....5
..3....6....0....7....1....1....4....1....2....1....7....6....7....6....3....5
		

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = 43*a(n-1) -798*a(n-2) +8358*a(n-3) -54201*a(n-4) +224427*a(n-5) -589112*a(n-6) +936452*a(n-7) -807408*a(n-8) +282240*a(n-9).
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: 4*x*(2 - 70*x + 1029*x^2 - 8253*x^3 + 39228*x^4 - 112119*x^5 + 185785*x^6 - 160106*x^7 + 53244*x^8) / ((1 - x)*(1 - 2*x)*(1 - 3*x)*(1 - 4*x)*(1 - 5*x)*(1 - 6*x)*(1 - 7*x)^2*(1 - 8*x)).
a(n) = (-980 - 147*2^(2+n) - 245*2^(1+2*n) - 490*3^n - 245*2^(2+n)*3^n - 588*5^n + 7818*7^n + 735*8^n + 120*7^n*n) / 5880.
(End)

A267472 Number of length-4 0..n arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

12, 62, 204, 515, 1096, 2072, 3592, 5829, 8980, 13266, 18932, 26247, 35504, 47020, 61136, 78217, 98652, 122854, 151260, 184331, 222552, 266432, 316504, 373325, 437476, 509562, 590212, 680079, 779840, 890196, 1011872, 1145617, 1292204
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Row 4 of A267471.

Examples

			Some solutions for n=7:
..2....1....5....5....0....2....5....6....3....4....0....0....3....3....2....3
..6....5....2....5....6....4....2....0....6....5....6....3....0....2....5....4
..0....2....3....0....3....1....0....4....3....1....4....0....5....5....6....7
..1....7....1....0....7....1....3....7....5....0....3....0....2....5....4....4
		

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = n^4 + (17/6)*n^3 + 4*n^2 + (19/6)*n + 1.
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: x*(12 + 2*x + 14*x^2 - 5*x^3 + 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)

A267473 Number of length-5 0..n arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

21, 160, 712, 2285, 5921, 13216, 26440, 48657, 83845, 137016, 214336, 323245, 472577, 672680, 935536, 1274881, 1706325, 2247472, 2918040, 3739981, 4737601, 5937680, 7369592, 9065425, 11060101, 13391496, 16100560, 19231437, 22831585
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Row 5 of A267471.

Examples

			Some solutions for n=7:
..7....1....4....4....7....0....0....7....1....2....4....7....5....6....3....4
..4....0....6....3....7....6....1....2....5....4....4....1....6....1....7....6
..4....1....7....1....7....3....7....4....1....5....2....4....1....4....7....3
..0....3....4....7....1....2....0....1....2....2....1....7....3....7....3....5
..2....6....4....5....5....7....3....1....4....5....4....2....7....7....5....5
		

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = n^5 + (37/12)*n^4 + (11/2)*n^3 + (77/12)*n^2 + 4*n + 1.
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: x*(21 + 34*x + 67*x^2 - 7*x^3 + 6*x^4 - 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)

A267474 Number of length-6 0..n arrays with no following elements larger than the first repeated value.

Original entry on oeis.org

38, 418, 2490, 10119, 31880, 83972, 193852, 404589, 779938, 1410134, 2418406, 3968211, 6271188, 9595832, 14276888, 20725465, 29439870, 41017162, 56165426, 75716767, 100641024, 132060204, 171263636, 219723845, 279113146, 351320958
Offset: 1

Views

Author

R. H. Hardin, Jan 15 2016

Keywords

Comments

Row 6 of A267471.

Examples

			Some solutions for n=7:
..0....6....6....4....1....2....0....0....2....0....2....4....0....2....6....4
..5....3....3....2....4....1....7....1....0....6....1....5....2....0....5....6
..1....2....5....5....0....6....2....7....2....7....6....3....6....1....7....2
..6....6....6....2....2....5....3....3....6....7....7....0....2....0....0....0
..1....2....1....6....6....7....7....1....6....3....7....4....3....5....3....7
..5....5....0....1....6....4....2....6....6....1....1....7....1....0....1....4
		

Crossrefs

Cf. A267471.

Formula

Empirical: a(n) = n^6 + (197/60)*n^5 + 7*n^4 + (43/4)*n^3 + 10*n^2 + (149/30)*n + 1.
Conjectures from Colin Barker, Feb 05 2018: (Start)
G.f.: x*(38 + 152*x + 362*x^2 + 137*x^3 + 37*x^4 - 7*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)
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