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 1-5 of 5 results.

A362258 Triangle read by rows: T(n,k) is the maximum number of ways in which a set of integer-sided squares can tile an n X k rectangle, up to rotations and reflections, 0 <= k <= n.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 4, 1, 1, 2, 4, 13, 20, 1, 1, 4, 8, 33, 125, 277, 1, 1, 6, 12, 72, 403, 2505, 7855, 1, 1, 9, 22, 204, 1438, 12069, 101587, 487662
Offset: 0

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Author

Pontus von Brömssen, Apr 15 2023

Keywords

Examples

			Triangle begins:
  n\k| 0  1  2  3   4    5     6      7      8
  ---+----------------------------------------
  0  | 1
  1  | 1  1
  2  | 1  1  1
  3  | 1  1  1  1
  4  | 1  1  2  2   4
  5  | 1  1  2  4  13   20
  6  | 1  1  4  8  33  125   277
  7  | 1  1  6 12  72  403  2505   7855
  8  | 1  1  9 22 204 1438 12069 101587 487662
See A362142 for an illustration of T(5,4) = 13.
The following table shows which sets of squares can tile the n X k rectangle in T(n,k) ways. A list x_1, ..., x_j represents a set of x_1 squares of side 1, ..., x_j squares of side j. When there are multiple solutions they are shown on separate lines. For (n,k) = (4,3), for example, the maximum number T(4,3) = 2 of tilings is obtained both for the set of 8 squares of side 1 and 1 square of side 2, and for the set of 4 squares of side 1 and 2 squares of side 2.
  n\k| 1   2      3     4     5     6      7       8
  ---+------------------------------------------------
  1  | 1
  2  | 2  4
     |    0,1
  3  | 3  6     9
     |    2,1   5,1
     |          0,0,1
  4  | 4  4,1   8,1    8,2
     |          4,2
  5  | 5  6,1   7,2   12,2  13,3
     |    2,2
  6  | 6  4,2  10,2   12,3  14,4  20,4
  7  | 7  6,2  13,2   12,4  19,4  22,5  25,6
  8  | 8  8,2  12,3   16,4  20,5  24,6  23,6,1  27,7,1
		

Crossrefs

Main diagonal: A362259.
Columns: A000012 (k = 0,1), A362260 (k = 2), A362261 (k = 3), A362262 (k = 4), A362263 (k = 5).
Cf. A227690, A361221 (rectangular pieces), A362142.

Formula

T(n,k) >= A362142(n,k)/4 if n != k.
T(n,n) >= A362142(n,n)/8.

A362144 Maximum number of ways in which a set of integer-sided squares can tile an n X 3 rectangle.

Original entry on oeis.org

1, 1, 2, 4, 6, 12, 24, 40, 80, 160, 280, 560, 1120, 2240, 4480, 10080, 20160, 40320, 88704, 177408, 354816, 768768, 1537536, 3075072, 6589440, 13178880, 26357760, 56010240, 112020480, 224040960, 504092160, 1064194560, 2128389120, 4729753600, 9932482560
Offset: 0

Views

Author

Pontus von Brömssen, Apr 10 2023

Keywords

Crossrefs

Third column of A362142.
Cf. A002478, A361219 (rectangular pieces).

Formula

a(n) = max_{3*i+2*j<=n} C(i,j,n-3*i-2*j)*2^j, where C(i,j,k) is the trinomial coefficient (i+j+k)!/(i!*j!*k!). (i and j correspond to the number of squares of side lengths 3 and 2, respectively.)

A362145 Maximum number of ways in which a set of integer-sided squares can tile an n X 4 rectangle.

Original entry on oeis.org

1, 1, 3, 6, 16, 37, 105, 250, 726, 1824, 5148, 13406, 37150, 99246, 271533, 739222, 2003686, 5534352, 14894898, 41614480, 112569696, 329633400, 939351720, 2713971172, 7790778688, 22262413872, 64295778000, 182043931368, 528451813656, 1484599951100, 4328456538812
Offset: 0

Views

Author

Pontus von Brömssen, Apr 10 2023

Keywords

Crossrefs

Fourth column of A362142.
Cf. A054856, A361220 (rectangular pieces).

A362146 Maximum number of ways in which a set of integer-sided squares can tile an n X 5 rectangle.

Original entry on oeis.org

1, 1, 4, 12, 37, 140, 454, 1566, 5670, 18738, 70800, 263002, 1065240, 4146500, 15269976, 61593260, 233206636, 879932068, 3442083056, 12794936028, 49150133908, 188187379818, 690417160564, 2688772826468, 10355819787218, 42350139855568, 167122149149460
Offset: 0

Views

Author

Pontus von Brömssen, Apr 10 2023

Keywords

Crossrefs

Fifth column of A362142.

A362143 Maximum number of ways in which a set of integer-sided squares can tile an n X n square.

Original entry on oeis.org

1, 1, 1, 4, 16, 140, 1987, 62266, 3899340, 508317004, 108388350636, 44608244030240, 39116330784279236
Offset: 0

Views

Author

Pontus von Brömssen, Apr 10 2023

Keywords

Crossrefs

Main diagonal of A362142.
Cf. A034295, A045846, A361217 (rectangular pieces).
Showing 1-5 of 5 results.