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.

A368660 Square array read by antidiagonals; the n-th row is the decimal expansion of the probability that the free polyomino with binary code A246521(n+1) appears in diffusion-limited aggregation on the square lattice.

Original entry on oeis.org

1, 0, 1, 0, 0, 0, 0, 0, 5, 0, 0, 0, 7, 4, 0, 0, 0, 2, 2, 4, 0, 0, 0, 6, 7, 2, 0, 0, 0, 0, 8, 3, 6, 5, 2, 0, 0, 0, 7, 1, 4, 4, 0, 1, 0, 0, 0, 4, 2, 9, 6, 4, 5, 1, 0, 0, 0, 8, 5, 3, 2, 3, 1, 6, 1, 0, 0, 0, 9, 1, 9, 9, 0, 7, 2, 3, 0, 0, 0, 0, 0, 0, 5, 4, 0, 7, 7, 2, 6, 0, 0
Offset: 1

Views

Author

Pontus von Brömssen, Jan 02 2024

Keywords

Comments

Given the current set of cells in a diffusion-limited aggregation process on the square lattice, with new cells coming in from infinity, the probability that the next cell appears in a given position can be found by "Spitzer's recipe" (see Spitzer (1976) and Wolf (1991)). These probabilities can then be aggregated to probabilities for each polyomino to appear.
Each row corresponds to a number in the field Q(Pi), i.e., a number of the form (Sum_{i=0..j} p_i*Pi^i)/(Sum_{i=0..k} q_i*Pi^i), with p_i and q_i integers.
Rows A130866(k-1)+1 to A130866(k) correspond to k-celled polyominoes, k >= 2. The sum of the numbers on those rows is 1.

Examples

			Array begins:
  1.00000000000000000000... (monomino)
  1.00000000000000000000... (domino)
  0.57268748908837848701... (L tromino)
  0.42731251091162151298... (I tromino)
  0.42649395750130487018... (L tetromino)
  0.05462942885357382723... (square tetromino)
  0.20430093094721062115... (T tetromino)
  0.15177943827373482673... (S tetromino)
  0.16279624442417585468... (I tetromino)
  0.13219133154126607406... (P pentomino)
  0.06837364801045779482... (V pentomino)
  0.03733461160442202363... (W pentomino)
  0.14605587435506817264... (L pentomino)
  0.15786504558818518196... (Y pentomino)
  0.10529476741119453953... (N pentomino)
  0.04279427184030725060... (U pentomino)
  0.08270007323598911231... (T pentomino)
  0.10865945602909460112... (F pentomino)
  0.04929714951722524019... (Z pentomino)
  0.01279646275569121440... (X pentomino)
  0.05663730811109879467... (I pentomino)
  ...
		

References

  • Frank Spitzer, Principles of Random Walk, 2nd edition, Springer, 1976. See Chapter III.

Crossrefs

Cf. A000105, A130866, A246521, A368661, A368662, A368863 (fixed polyominoes).
Corresponding sequences for internal diffusion-limited aggregation: A368386, A368387.

A368662 Square array read by antidiagonals; the n-th row is the decimal expansion of the maximum probability that a particular free polyomino with n cells appears in diffusion-limited aggregation on the square lattice.

Original entry on oeis.org

1, 0, 1, 0, 0, 0, 0, 0, 5, 0, 0, 0, 7, 4, 0, 0, 0, 2, 2, 1, 0, 0, 0, 6, 6, 5, 0, 0, 0, 0, 8, 4, 7, 6, 0, 0
Offset: 1

Views

Author

Pontus von Brömssen, Jan 04 2024

Keywords

Comments

The n-th row is the decimal expansion of the maximum of the numbers corresponding to rows A130866(n-1)+1..A130866(n) of A368660. See A368660 for details.

Examples

			Array begins:
  1.00000000000000000000... (1st row of A368660)
  1.00000000000000000000... (2nd row of A368660)
  0.57268748908837848701... (3rd row of A368660)
  0.42649395750130487018... (5th row of A368660)
  0.15786504558818518196... (14th row of A368660)
  0.06192086165513502549... (36th row of A368660)
  ...
The corresponding polyominoes for 1 <= n <= 6 are (all these are unique):
                    _                   _
        _    _     | |       _         | |
   _   | |  | |_   | |_    _| |_ _    _| |_ _
  |_|  |_|  |_ _|  |_ _|  |_ _ _ _|  |_ _ _ _|
		

Crossrefs

Cf. A130866, A368390 (internal diffusion-limited aggregation), A368660, A368661 (minimum), A368663 (row 3), A368665 (row 4), A368865 (fixed polyominoes).

A368666 Decimal expansion of the probability that the square tetromino appears when the 4th cell is added in diffusion-limited aggregation on the square lattice.

Original entry on oeis.org

0, 5, 4, 6, 2, 9, 4, 2, 8, 8, 5, 3, 5, 7, 3, 8, 2, 7, 2, 3, 9, 9, 1, 1, 0, 2, 2, 1, 3, 9, 5, 1, 1, 9, 3, 7, 6, 9, 0, 2, 2, 9, 7, 0, 8, 2, 6, 8, 2, 4, 6, 9, 0, 6, 3, 5, 9, 2, 8, 2, 0, 4, 0, 1, 6, 8, 3, 3, 0, 0, 4, 1, 9, 0, 8, 2, 8, 8, 6, 6, 1, 3, 6, 9, 8, 6, 6, 2, 2, 1, 5, 6, 7, 5, 4, 6, 7, 1, 3, 5
Offset: 0

Views

Author

Pontus von Brömssen, Jan 04 2024

Keywords

Comments

See A368660 for details.

Examples

			0.054629428853573827239911022139511937690229708268246906359282...
		

Crossrefs

6th row of A368660.
4th row of A368661.

Formula

Equals (7680 - 10744*Pi + 5572*Pi^2 - 1272*Pi^3 + 108*Pi^4)/(21504 - 32000*Pi + 17368*Pi^2 - 4101*Pi^3 + 357*Pi^4).

A368667 Decimal expansion of the probability that the T tetromino appears when the 4th cell is added in diffusion-limited aggregation on the square lattice.

Original entry on oeis.org

2, 0, 4, 3, 0, 0, 9, 3, 0, 9, 4, 7, 2, 1, 0, 6, 2, 1, 1, 5, 2, 7, 4, 5, 0, 7, 4, 6, 1, 4, 7, 5, 7, 7, 0, 6, 8, 3, 4, 9, 5, 3, 5, 2, 4, 7, 0, 5, 6, 3, 7, 9, 1, 1, 2, 0, 4, 2, 3, 8, 1, 2, 9, 5, 7, 4, 2, 7, 2, 6, 9, 8, 6, 2, 9, 8, 8, 1, 5, 5, 9, 9, 0, 6, 1, 1, 2, 4, 8, 7, 8, 5, 9, 8, 2, 3, 1, 1, 0, 7
Offset: 0

Views

Author

Pontus von Brömssen, Jan 04 2024

Keywords

Comments

See A368660 for details.

Examples

			0.204300930947210621152745074614757706834953524705637911204238...
		

Crossrefs

7th row of A368660.

Formula

Equals (286720 - 520576*Pi + 365408*Pi^2 - 125052*Pi^3 + 20982*Pi^4 - 1386*Pi^5)/(1204224 - 2114560*Pi + 1452608*Pi^2 - 490176*Pi^3 + 81507*Pi^4 - 5355*Pi^5).

A368668 Decimal expansion of the probability that the skew tetromino appears when the 4th cell is added in diffusion-limited aggregation on the square lattice.

Original entry on oeis.org

1, 5, 1, 7, 7, 9, 4, 3, 8, 2, 7, 3, 7, 3, 4, 8, 2, 6, 7, 3, 8, 9, 8, 9, 3, 4, 0, 9, 3, 2, 0, 3, 2, 8, 6, 2, 5, 9, 1, 1, 3, 1, 0, 8, 2, 4, 6, 1, 1, 7, 0, 1, 6, 3, 2, 9, 0, 6, 6, 7, 9, 9, 1, 8, 8, 4, 1, 3, 9, 7, 1, 5, 7, 4, 6, 7, 1, 4, 4, 3, 0, 8, 8, 6, 0, 5, 9, 8, 6, 5, 5, 3, 4, 0, 5, 3, 1, 7, 6, 1
Offset: 0

Views

Author

Pontus von Brömssen, Jan 04 2024

Keywords

Comments

See A368660 for details.

Examples

			0.151779438273734826738989340932032862591131082461170163290667...
		

Crossrefs

8th row of A368660.

Formula

Equals (3200 - 5560*Pi + 3370*Pi^2 - 867*Pi^3 + 81*Pi^4)/(21504 - 32000*Pi + 17368*Pi^2 - 4101*Pi^3 + 357*Pi^4).

A368669 Decimal expansion of the probability that the straight tetromino appears when the 4th cell is added in diffusion-limited aggregation on the square lattice.

Original entry on oeis.org

1, 6, 2, 7, 9, 6, 2, 4, 4, 4, 2, 4, 1, 7, 5, 8, 5, 4, 6, 8, 2, 5, 1, 2, 0, 0, 1, 0, 2, 4, 5, 4, 8, 6, 7, 0, 8, 7, 7, 5, 0, 0, 4, 7, 8, 9, 0, 8, 2, 1, 1, 3, 6, 4, 3, 2, 8, 9, 1, 6, 1, 8, 9, 1, 2, 1, 8, 9, 2, 5, 1, 4, 2, 0, 3, 9, 6, 5, 6, 4, 4, 5, 3, 8, 2, 6, 1, 5, 4, 2, 1, 0, 2, 5, 2, 1, 8, 5, 0, 4
Offset: 0

Views

Author

Pontus von Brömssen, Jan 04 2024

Keywords

Comments

See A368660 for details.

Examples

			0.162796244424175854682512001024548670877500478908211364328916...
		

Crossrefs

9th row of A368660.

Programs

  • Mathematica
    First[RealDigits[2*(Pi - 4)^2*(3*Pi - 10)/((5*Pi - 16)*(7*Pi - 24)*(15*Pi - 56)), 10, 100]] (* Paolo Xausa, Nov 12 2024 *)

Formula

Equals (320 - 256*Pi + 68*Pi^2 - 6*Pi^3)/(21504 - 18752*Pi + 5440*Pi^2 - 525*Pi^3).
Showing 1-6 of 6 results.