A263816
T(n,k)=Number of (n+1)X(k+1) arrays of permutations of 0..(n+1)*(k+1)-1 with each element having index change (+-,+-) 0,0 0,1 0,2 or 1,0.
Original entry on oeis.org
9, 82, 32, 572, 948, 121, 3682, 18776, 11305, 450, 25001, 333429, 643905, 134028, 1681, 170946, 6425985, 31916832, 21876416, 1590733, 6272, 1157993, 124854432, 1746531193, 3019386508, 744805993, 18875976, 23409, 7844192, 2392853088
Offset: 1
Some solutions for n=2 k=4
..0..1..3..2..4....0..3..2..8..4....0..6..2..8..4....0..3..2..8..4
..5..6..7..8..9....6..1.12..9..7....7..1..9..3.14....5..1..9..6..7
.12.10.11.14.13....5.10.13.11.14....5.11.10.13.12...12.10.11.14.13
A233308
Number A(n,k) of tilings of a k X k X n box using k*n bricks of shape k X 1 X 1; square array A(n,k), n>=0, k>=1, read by antidiagonals.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 1, 2, 9, 1, 1, 2, 4, 32, 1, 1, 2, 4, 21, 121, 1, 1, 2, 4, 8, 92, 450, 1, 1, 2, 4, 8, 45, 320, 1681, 1, 1, 2, 4, 8, 16, 248, 1213, 6272, 1, 1, 2, 4, 8, 16, 93, 1032, 4822, 23409, 1, 1, 2, 4, 8, 16, 32, 668, 3524, 18556, 87362, 1, 1, 2, 4, 8, 16, 32, 189, 3440, 13173, 70929, 326041, 1
Offset: 0
Square array A(n,k) begins:
1, 1, 1, 1, 1, 1, ...
1, 2, 2, 2, 2, 2, ...
1, 9, 4, 4, 4, 4, ...
1, 32, 21, 8, 8, 8, ...
1, 121, 92, 45, 16, 16, ...
1, 450, 320, 248, 93, 32, ...
1, 1681, 1213, 1032, 668, 189, ...
1, 6272, 4822, 3524, 3440, 1832, ...
1, 23409, 18556, 13173, 13728, 11976, ...
-
b:= proc(n, l) option remember; local d, t, k; d:= isqrt(nops(l));
if max(l[])>n then 0 elif n=0 then 1
elif min(l[])>0 then t:=min(l[]); b(n-t, map(x->x-t, l))
else for k while l[k]>0 do od; b(n, subsop(k=d, l))+
`if`(irem(k,d)=1 and {seq(l[k+j], j=1..d-1)}={0},
b(n, [seq(`if`(h-k=0, 1, l[h]), h=1..nops(l))]), 0)+
`if`(k<=d and {seq(l[k+d*j], j=1..d-1)}={0},
b(n, [seq(`if`(irem(h-k, d)=0, 1, l[h]), h=1..nops(l))]), 0)
fi
end:
A:= (n, k)-> `if`(k>n, 2^n, b(n, [0$k^2])):
seq(seq(A(n, 1+d-n), n=0..d), d=0..11);
-
b[n_, l_] := b[n, l] = Module[{d, t, k}, d= Sqrt[Length[l]]; Which[ Max[l]>n, 0, n==0, 1, Min[l]>0, t=Min[l]; b[n-t, l-t], True, k=Position[l, 0, 1][[1, 1]]; b[n, ReplacePart[l, k->d]]+ If[Mod[k, d]==1 && Union[ Table[ l[[k+j]], {j, 1, d-1}]] == {0}, b[n, Table[ If [h-k=0, 1, l[[h]] ], {h, 1, Length[l]}]], 0]+ If[k <= d && Union[ Table[ l[[k+d*j]], {j, 1, d-1}]] == {0}, b[n, Table[ If[ Mod[h-k, d] == 0, 1, l[[h]] ], {h, 1, Length[l]}]], 0] ] ]; a[n_, k_]:= If[k>n, 2^n, b[n, Array[0&, k^2]]]; Table[Table[a[n, 1+d-n], {n, 0, d}], {d, 0, 11}] // Flatten (* Jean-François Alcover, Dec 13 2013, translated from Maple *)
A360064
Number of 3-dimensional tilings of a 2 X 2 X n box using 1 X 1 X 1 cubes and trominos (L-shaped connection of 3 cubes).
Original entry on oeis.org
1, 5, 89, 1177, 16873, 237977, 3366793, 47599097, 673035625, 9516252633, 134553882441, 1902506043833, 26900227288361, 380352114739609, 5377937177440009, 76040613721296249, 1075165950495479017, 15202163218500810073, 214948926180739194569
Offset: 0
4 rotations:
___ ___ ___ ___
| | | | | | (cross sections)
| |___| |___|___|
| | | | |
|_______| |___|___| a(1) = 4 + 1 = 5.
-
LinearRecurrence[{13, 20, -64, 112, 224, -128}, {1, 5, 89, 1177, 16873, 237977}, 25] (* Paolo Xausa, Oct 02 2024 *)
A360065
Number of 3-dimensional tilings of a 2 X 2 X n box using 2 X 1 X 1 dominos and trominos (L-shaped connection of 3 cubes).
Original entry on oeis.org
1, 2, 45, 412, 4705, 50374, 549109, 5955544, 64683649, 702259786, 7625147293, 82791470836, 898931464993, 9760376329678, 105975828745957, 1150659965697328, 12493588746237697, 135652375422278290, 1472880803124594061, 15992184812239930060, 173639288800074705121
Offset: 0
a(2)=45
1) Two parallel trominos and one domino: There are 3 middle axes of the 2 X 2 cube with 4 rotation images each: 12 images.
___ ___ ___ ___
/__ /| / /| /__ / /|
/__ /| |___ /__ / | /__ /__ / |
| | |/__ /| | | / | | | /|
| |/__ /| | + |___|/ = | |___|/| |
| | |/ | | |/
|_______|/ |_______|/
2) Two "linked" trominos and one domino: 12 rotation images and, as there is no symmetry plane, 12 mirror images: 24 images.
___ ___ ___ ___
/ /| / /| / / /|
/__ / | _______ /__ / | /__ /__ / |
| | / /__ /| | | / | | | /|
| | | + | /__ / | + |___|/ = | |___|/ |
| | | |_| | / | | | /
|___|/ |___|/ |___|___|/
3) Using only dominos: A006253(2)=9 ways, Sum: a(2) = 12 + 24 + 9 = 45.
-
LinearRecurrence[{7, 42, 6, -81, 27}, {1, 2, 45, 412, 4705}, 25] (* Paolo Xausa, Oct 02 2024 *)
A233289
Number of tilings of a 3 X 3 X n box using 3n bricks of shape 3 X 1 X 1.
Original entry on oeis.org
1, 2, 4, 21, 92, 320, 1213, 4822, 18556, 70929, 273808, 1057020, 4069737, 15676666, 60424640, 232846801, 897164316, 3457096532, 13321674833, 51332757274, 197801848744, 762200458321, 2937024077340, 11317358546188, 43609682555721, 168043191679374
Offset: 0
- Alois P. Heinz, Table of n, a(n) for n = 0..1000
- R. J. Mathar, Tilings of rectangular regions by rectangular tiles: counts derived from transfer matrices, arXiv:1406.7788 [math.CO], 2014; eq. (40).
- Wikipedia, Jenga
- Index entries for linear recurrences with constant coefficients, signature (3,0,13,2,-11,-7,4,-3,1,-1)
-
gf:= (x^7-x^6+x^5-x^4+4*x^3+2*x^2+x-1)/(-x^10+x^9
-3*x^8+4*x^7-7*x^6-11*x^5+2*x^4+13*x^3+3*x-1):
a:= n-> coeff(series(gf, x, n+1), x, n):
seq(a(n), n=0..30);
A028452
Number of perfect matchings in graph P_{3} X P_{3} X P_{2n}.
Original entry on oeis.org
1, 229, 117805, 64647289, 35669566217, 19690797527709, 10870506600976757, 6001202979497804657, 3313042830624031354513, 1829008840116358153050197, 1009728374600381843221483965, 557433823481589253332775648233, 307738670509229621147710358375321
Offset: 0
- Alois P. Heinz, Table of n, a(n) for n = 0..300
- Per Hakan Lundow, Computation of matching polynomials and the number of 1-factors in polygraphs, Research report, No 12, 1996, Department of Math., Umea University, Sweden.
- Per Hakan Lundow, Enumeration of matchings in polygraphs, 1998.
- R. J. Mathar, Tilings of rectangular regions by rectangular tiles: Counts derived from transfer matrices, arXiv:1406.7788 [math.CO], (2014), eq (38).
- James Propp, A reciprocity theorem for domino tilings, El. J. Combin. 8 (2001) #R18.
- J. de Ruiter, Counting Domino Coverings and Chessboard Cycles, 2010. [Broken link]
A233291
Number of tilings of a 4 X 4 X n box using 4n bricks of shape 4 X 1 X 1.
Original entry on oeis.org
1, 2, 4, 8, 45, 248, 1032, 3524, 13173, 54274, 228712, 917992, 3608665, 14286188, 57438652, 231343468, 926921081, 3700936774, 14793198332, 59241396140, 237333611629, 950127617692, 3801974385964, 15215432779936, 60907523900693, 243826775063490, 976008753961184
Offset: 0
A233294
Number of tilings of a 5 X 5 X n box using 5n bricks of shape 5 X 1 X 1.
Original entry on oeis.org
1, 2, 4, 8, 16, 93, 668, 3440, 13728, 46252, 172577, 739002, 3417464, 15550336, 65956764, 271247405, 1119519052, 4726308568, 20348072952, 87598217268, 373660404281, 1581318625634, 6680851858676, 28326586367464, 120536842633616, 513461699313993
Offset: 0
A359886
Number of 3-dimensional tilings of a 2 X 2 X n box using 2 X 2 X 1 plates and trominos (three 1 X 1 X 1 cubes).
Original entry on oeis.org
1, 1, 3, 49, 231, 789, 4771, 27225, 122799, 607469, 3255979, 16253649, 80098519, 409480005, 2079921395, 10411734921, 52523676351, 266059774429, 1341128940795, 6758479842689, 34138205819239, 172324729379509, 869131661400259, 4386075013348025, 22138673661637327
Offset: 0
a(3) = 49.
The number of tilings only using plates is A001045(3) = 5.
The number of tilings only using trominos is A359885(1) = 44.
These terms are to be added as, for n=3, there is no tiling using both tiles.
-
LinearRecurrence[{2, 1, 58, 72, 32, -128}, {1, 1, 3, 49, 231, 789}, 30] (* Paolo Xausa, Jun 24 2024 *)
-
/* See link "Maxima code". */
A028454
Number of perfect matchings in graph P_{4} X P_{4} X P_{n}.
Original entry on oeis.org
1, 36, 32000, 10885344, 5051532105, 2132137503232, 932814464901633, 403325499406267520, 175220727982196365632, 75996591204223021534740, 32983893365927357595999561, 14312021563707748863632803328, 6210770058902782255142931025577
Offset: 0
- Alois P. Heinz, Table of n, a(n) for n = 0..100
- Per Hakan Lundow, Computation of matching polynomials and the number of 1-factors in polygraphs, Research report, No 12, 1996, Department of Math., Umea University, Sweden.
- Per Hakan Lundow, Enumeration of matchings in polygraphs, 1998.
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