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 1-6 of 6 results.

A265233 Number of 3 X n arrays containing n copies of 0..2 with no equal vertical neighbors and new values introduced sequentially from 0.

Original entry on oeis.org

1, 1, 7, 56, 495, 4686, 46456, 475392, 4976271, 52977890, 571434402, 6228357312, 68468597544, 758063599632, 8443936740960, 94545206802816, 1063391499647631, 12007844534804202, 136068111377744686, 1546682224461979920, 17630279034262961010, 201470426310372260580
Offset: 0

Views

Author

R. H. Hardin, Dec 06 2015

Keywords

Comments

Row 3 of A265232.

Examples

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

Crossrefs

Cf. A265232.

Formula

Conjecture: n^2*a(n) +(-19*n^2+19*n-6)*a(n-1) +96*(n-1)^2*a(n-2) -144*(n-1)*(n-2)*a(n-3)=0. - R. J. Mathar, Dec 08 2015
Conjecture: a(n) ~ 2^(2*n - 1) * 3^(n - 1/2) / (Pi*n). - Vaclav Kotesovec, Mar 08 2023
If conjectured recurrence is true then ogf = (hypergeom([1/3,2/3],[1],27*x*(4*x-1)^2)+5)/6. - Mark van Hoeij, Nov 28 2024

Extensions

a(0)=1 prepended by Alois P. Heinz, Nov 28 2024

A265234 Number of 4 X n arrays containing n copies of 0..4-1 with no equal vertical neighbors and new values introduced sequentially from 0.

Original entry on oeis.org

1, 43, 2592, 184740, 14439456, 1196114464, 103142395392, 9160513923648, 832211576040960, 76971887847571968, 7223525356855099392, 686117529041422350336, 65834293657115919826944, 6371837299781950752276480
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2015

Keywords

Examples

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

Crossrefs

Row 4 of A265232.

Formula

From Manuel Kauers and Christoph Koutschan, Mar 01 2023: (Start)
a(n) = coefficient of x^n*y^n*z^n in (1/24)*(2*x^2 + 6*x*y + 6*x^2*y + 2*y^2 + 6*x*y^2 + 2*x^2*y^2 + 6*x*z + 6*x^2*z + 6*y*z + 24*x*y*z + 6*x^2*y*z + 6*y^2*z + 6*x*y^2*z + 2*z^2 + 6*x*z^2 + 2*x^2*z^2 + 6*y*z^2 + 6*x*y*z^2 + 2*y^2*z^2)^n.
Recurrence of order 6 and degree 6: 5*(n + 5)*(832*n^2 + 5785*n + 8460)*(n + 6)^3*a(n + 6) - 4*(n + 5)*(126464*n^5 + 2941016*n^4 + 26840735*n^3 + 119399663*n^2 + 256228730*n + 208319000)*a(n + 5) + 16*(310336*n^6 + 7680621*n^5 + 78610375*n^4 + 426421788*n^3 + 1294537774*n^2 + 2087600280*n + 1398239904)*a(n + 4) + 128*(n + 4)*(1161472*n^5 + 24822356*n^4 + 207271023*n^3 + 841828441*n^2 + 1653171497*n + 1242989235)*a(n + 3) - 768*(n + 3)*(n + 4)*(3709888*n^4 + 58438003*n^3 + 333112832*n^2 + 813878537*n + 716118600)*a(n + 2) + 9216*(n + 2)*(n + 3)*(n + 4)*(1743872*n^3 + 20496944*n^2 + 74692297*n + 84692065)*a(n + 1) - 34836480*(n + 1)*(n + 2)*(n + 3)*(n + 4)*(832*n^2 + 7449*n + 15077)*a(n) = 0. (End)
a(n) ~ 2^(2*n - 19/2) * 3^(3*n + 7/2) / (Pi^(3/2) * n^(3/2)). - Vaclav Kotesovec, Mar 08 2023

A265229 Number of n X 2 arrays containing 2 copies of 0..n-1 with no equal vertical neighbors and new values introduced sequentially from 0.

Original entry on oeis.org

1, 2, 7, 43, 372, 4027, 51871, 773186, 13083385, 247698481, 5186925696, 119023766737, 2969884019977, 80056947698498, 2318432654628847, 71785166633148187, 2366425763631216756, 82748313392542136011
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2015

Keywords

Examples

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

Crossrefs

Column 2 of A265232.

A265230 Number of nX3 arrays containing 3 copies of 0..n-1 with no equal vertical neighbors and new values introduced sequentially from 0.

Original entry on oeis.org

1, 4, 56, 2592, 222850, 29357385, 5460708807, 1360701035812, 437196618018421, 175924945354032520
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2015

Keywords

Comments

Column 3 of A265232.

Examples

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

Crossrefs

Cf. A265232.

A265231 Number of nX4 arrays of permutations of 4 copies of 0..n-1 with no equal vertical neighbors and new values introduced sequentially from 0.

Original entry on oeis.org

1, 8, 495, 184740, 164933040, 277778385204, 785263649477535
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2015

Keywords

Comments

Column 4 of A265232.

Examples

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

Crossrefs

Cf. A265232.

A265235 Number of 5Xn arrays containing n copies of 0..5-1 with no equal vertical neighbors and new values introduced sequentially from 0.

Original entry on oeis.org

1, 372, 222850, 164933040, 137409486772, 123531282436770, 117115132044401100, 115473661661749763520, 117339977328886229407120, 122120444042051198450868012, 129586955944964431527460363320
Offset: 1

Views

Author

R. H. Hardin, Dec 06 2015

Keywords

Comments

Row 5 of A265232.

Examples

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

Crossrefs

Cf. A265232.
Showing 1-6 of 6 results.