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 1-8 of 8 results.

A269431 Number of length-n 0..4 arrays with no repeated value greater than the previous repeated value.

Original entry on oeis.org

5, 25, 125, 615, 2995, 14455, 69235, 329430, 1558430, 7334806, 34364270, 160340610, 745362730, 3453222850, 15949215754, 73454841775, 337413819915, 1546145183895, 7068979186035, 32251365241137, 146853223312325, 667445619383425
Offset: 1

Views

Author

R. H. Hardin, Feb 26 2016

Keywords

Examples

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

Crossrefs

Column 4 of A269435.

Formula

Empirical: a(n) = 20*a(n-1) - 155*a(n-2) + 560*a(n-3) - 810*a(n-4) - 136*a(n-5) + 810*a(n-6) + 560*a(n-7) + 155*a(n-8) + 20*a(n-9) + a(n-10).
Empirical g.f.: x*(5 - 75*x + 400*x^2 - 810*x^3 + 120*x^4 + 810*x^5 + 560*x^6 + 155*x^7 + 20*x^8 + x^9) / (1 - 4*x - x^2)^5. - Colin Barker, Jan 21 2019

A269432 Number of length-n 0..5 arrays with no repeated value greater than the previous repeated value.

Original entry on oeis.org

6, 36, 216, 1281, 7536, 44021, 255576, 1475871, 8482276, 48543777, 276756312, 1572394697, 8905537932, 50293202487, 283276001872, 1591658418642, 8922925364502, 49917266140917, 278703080519352, 1553227427718978
Offset: 1

Views

Author

R. H. Hardin, Feb 26 2016

Keywords

Comments

Column 5 of A269435.

Examples

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

Crossrefs

Cf. A269435.

Formula

Empirical: a(n) = 30*a(n-1) -369*a(n-2) +2350*a(n-3) -7890*a(n-4) +11550*a(n-5) +895*a(n-6) -11550*a(n-7) -7890*a(n-8) -2350*a(n-9) -369*a(n-10) -30*a(n-11) -a(n-12)

A269433 Number of length-n 0..6 arrays with no repeated value greater than the previous repeated value.

Original entry on oeis.org

7, 49, 343, 2380, 16408, 112476, 767172, 5209554, 35236110, 237479970, 1595378190, 10686193980, 71386033740, 475694666700, 3162645548916, 20982275486907, 138930896958189, 918219765681883, 6058251819231325, 39906814296599320
Offset: 1

Views

Author

R. H. Hardin, Feb 26 2016

Keywords

Comments

Column 6 of A269435.

Examples

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

Crossrefs

Cf. A269435.

Formula

Empirical: a(n) = 42*a(n-1) -749*a(n-2) +7308*a(n-3) -41601*a(n-4) +133686*a(n-5) -198037*a(n-6) -2136*a(n-7) +198037*a(n-8) +133686*a(n-9) +41601*a(n-10) +7308*a(n-11) +749*a(n-12) +42*a(n-13) +a(n-14)

A269434 Number of length-n 0..7 arrays with no repeated value greater than the previous repeated value.

Original entry on oeis.org

8, 64, 512, 4068, 32152, 252932, 1981512, 15465934, 120310016, 933059856, 7216323640, 55670133422, 428465939112, 3290601897928, 25221303496496, 192953793764769, 1473623863797808, 11236105478130612, 85542959337048488
Offset: 1

Views

Author

R. H. Hardin, Feb 26 2016

Keywords

Comments

Column 7 of A269435.

Examples

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

Crossrefs

Cf. A269435.

Formula

Empirical: a(n) = 56*a(n-1) -1364*a(n-2) +18816*a(n-3) -159866*a(n-4) +846328*a(n-5) -2642416*a(n-6) +3954888*a(n-7) -157507*a(n-8) -3954888*a(n-9) -2642416*a(n-10) -846328*a(n-11) -159866*a(n-12) -18816*a(n-13) -1364*a(n-14) -56*a(n-15) -a(n-16)

A269436 Number of length-4 0..n arrays with no repeated value greater than the previous repeated value.

Original entry on oeis.org

15, 78, 250, 615, 1281, 2380, 4068, 6525, 9955, 14586, 20670, 28483, 38325, 50520, 65416, 83385, 104823, 130150, 159810, 194271, 234025, 279588, 331500, 390325, 456651, 531090, 614278, 706875, 809565, 923056, 1048080, 1185393, 1335775
Offset: 1

Views

Author

R. H. Hardin, Feb 26 2016

Keywords

Examples

			Some solutions for n=8:
..7. .8. .1. .4. .8. .5. .6. .6. .7. .0. .7. .7. .8. .5. .5. .0
..6. .3. .6. .3. .5. .3. .2. .4. .2. .7. .6. .1. .3. .3. .7. .3
..3. .8. .5. .0. .4. .7. .2. .7. .4. .7. .7. .2. .5. .0. .2. .4
..7. .2. .7. .0. .2. .1. .3. .4. .0. .8. .4. .6. .5. .0. .8. .1
		

Crossrefs

Row 4 of A269435.

Formula

Empirical: a(n) = n^4 + 4*n^3 + (11/2)*n^2 + (7/2)*n + 1.
Conjectures from Colin Barker, Jan 22 2019: (Start)
G.f.: x*(15 + 3*x + 10*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)

A269437 Number of length-5 0..n arrays with no repeated value greater than the previous repeated value.

Original entry on oeis.org

28, 222, 964, 2995, 7536, 16408, 32152, 58149, 98740, 159346, 246588, 368407, 534184, 754860, 1043056, 1413193, 1881612, 2466694, 3188980, 4071291, 5138848, 6419392, 7943304, 9743725, 11856676, 14321178, 17179372, 20476639, 24261720
Offset: 1

Views

Author

R. H. Hardin, Feb 26 2016

Keywords

Examples

			Some solutions for n=8:
..2. .3. .5. .5. .2. .7. .6. .3. .8. .3. .7. .2. .1. .8. .6. .8
..1. .4. .4. .3. .3. .4. .4. .4. .7. .5. .1. .2. .1. .1. .6. .2
..5. .0. .6. .4. .2. .8. .6. .0. .2. .0. .5. .4. .1. .0. .1. .7
..0. .2. .7. .6. .4. .4. .1. .0. .4. .7. .8. .3. .4. .3. .7. .4
..3. .3. .4. .7. .5. .1. .7. .3. .5. .3. .0. .4. .0. .6. .5. .8
		

Crossrefs

Row 5 of A269435.

Formula

Empirical: a(n) = n^5 + 5*n^4 + (17/2)*n^3 + 8*n^2 + (9/2)*n + 1.
Conjectures from Colin Barker, Jan 22 2019: (Start)
G.f.: x*(28 + 54*x + 52*x^2 - 19*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)

A269438 Number of length-6 0..n arrays with no repeated value greater than the previous repeated value.

Original entry on oeis.org

51, 622, 3674, 14455, 44021, 112476, 252932, 516189, 976135, 1735866, 2934526, 4754867, 7431529, 11260040, 16606536, 23918201, 33734427, 46698694, 63571170, 85242031, 112745501, 147274612, 190196684, 243069525, 307658351, 385953426
Offset: 1

Views

Author

R. H. Hardin, Feb 26 2016

Keywords

Examples

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

Crossrefs

Row 6 of A269435.

Formula

Empirical: a(n) = n^6 + 6*n^5 + 12*n^4 + (44/3)*n^3 + (23/2)*n^2 + (29/6)*n + 1.
Conjectures from Colin Barker, Jan 22 2019: (Start)
G.f.: x*(51 + 265*x + 391*x^2 + 14*x^3 + 5*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)

A269439 Number of length-7 0..n arrays with no repeated value greater than the previous repeated value.

Original entry on oeis.org

92, 1722, 13868, 69235, 255576, 767172, 1981512, 4566213, 9621220, 18861326, 34844052, 61247927, 103206208, 167701080, 264023376, 404302857, 604114092, 883162978, 1266058940, 1783177851, 2471620712, 3376273132, 4550970648
Offset: 1

Views

Author

R. H. Hardin, Feb 26 2016

Keywords

Examples

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

Crossrefs

Row 7 of A269435.

Formula

Empirical: a(n) = n^7 + 7*n^6 + 16*n^5 + (71/3)*n^4 + (139/6)*n^3 + (43/3)*n^2 + (35/6)*n + 1.
Conjectures from Colin Barker, Jan 22 2019: (Start)
G.f.: x*(92 + 986*x + 2668*x^2 + 1355*x^3 + 8*x^4 - 76*x^5 + 8*x^6 - x^7) / (1 - x)^8.
a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>8.
(End)
Showing 1-8 of 8 results.