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.

Previous Showing 11-15 of 15 results.

A246327 Total number of ON cells at stage 2n of two-dimensional 5-neighbor outer totalistic cellular automaton defined by "Rule 457".

Original entry on oeis.org

1, 9, 21, 57, 65, 81, 97, 165, 233, 221, 277, 361, 425, 441, 585, 777, 905, 777, 933, 1045, 1173, 1225, 1593, 1833, 1981, 1725, 1757, 2429, 2365, 2701, 2881, 3093, 3361, 3345, 3353, 3397, 3861, 4057, 4421, 4549, 4765, 5053, 5373, 5713, 5685, 5769, 6161, 6933, 7325, 7029, 7533, 7757, 8329, 7853
Offset: 0

Views

Author

N. J. A. Sloane, Aug 30 2014

Keywords

Comments

The number of ON cells at stage 2n+1 is infinite.

References

  • S. Wolfram, A New Kind of Science, Wolfram Media, 2002; pp. 173-175.

Crossrefs

Programs

  • Mathematica
    Map[Function[Apply[Plus, Flatten[ #1]]], CellularAutomaton[{ 457, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 130]] (* then take every other term *)
    ArrayPlot /@ CellularAutomaton[{457, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 23]

A246328 Total number of ON cells at stage 2n of two-dimensional 5-neighbor outer totalistic cellular automaton defined by "Rule 459".

Original entry on oeis.org

1, 9, 25, 32, 101, 57, 156, 153, 309, 185, 389, 345, 613, 460, 669, 721, 1120, 961, 965, 1104, 1337, 1237, 1500, 1524, 2136, 1824, 2232, 2260, 2640, 2649, 2736, 3092, 3689, 3144, 3688, 3932, 3937, 4228, 4488, 5013, 5112, 5012, 5748, 5945, 6440, 6216, 7073, 7396, 7932, 7412, 8201, 8348, 8696, 9237
Offset: 0

Views

Author

N. J. A. Sloane, Aug 30 2014

Keywords

Comments

The number of ON cells at stage 2n+1 is infinite.

References

  • S. Wolfram, A New Kind of Science, Wolfram Media, 2002; pp. 173-175.

Crossrefs

Programs

  • Mathematica
    Map[Function[Apply[Plus, Flatten[ #1]]], CellularAutomaton[{ 459, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 130]] (* then take every other term *)
    ArrayPlot /@ CellularAutomaton[{459, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 23]

A246332 a(n) = if n is even, number of ON cells at stage n of two-dimensional 5-neighbor outer totalistic cellular automaton defined by "Rule 461" or if n is odd, number of OFF cells.

Original entry on oeis.org

1, 1, 5, 5, 17, 9, 21, 21, 25, 33, 45, 49, 81, 69, 105, 81, 101, 101, 165, 141, 197, 185, 217, 209, 265, 245, 337, 269, 405, 325, 477, 389, 521, 461, 625, 469, 621, 485, 769, 585, 849, 737, 825, 705, 973, 713, 985, 841, 1089, 925, 1257, 969, 1229, 1093, 1265
Offset: 0

Views

Author

N. J. A. Sloane, Aug 30 2014

Keywords

References

  • S. Wolfram, A New Kind of Science, Wolfram Media, 2002; pp. 173-175.

Crossrefs

A246329 is a bisection.

Programs

  • Mathematica
    Map[Function[Apply[Plus, Flatten[ #1]]], CellularAutomaton[{ 461, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 130]] (* then subtract the odd-indexed terms from 131^2 *)
    ArrayPlot /@ CellularAutomaton[{461, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 23]

A271257 Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 324", based on the 5-celled von Neumann neighborhood.

Original entry on oeis.org

1, 5, 10, 22, 30, 54, 79, 119, 152, 196, 236, 324, 401, 501, 622, 798, 935, 1099, 1240, 1444, 1661, 1949, 2258, 2642, 2995, 3399, 3800, 4308, 4821, 5385, 5986, 6710, 7411, 8083, 8812, 9636, 10485, 11449, 12430, 13598, 14727, 15851, 16964, 18232, 19573, 20997
Offset: 0

Views

Author

Robert Price, Apr 02 2016

Keywords

Comments

Initialized with a single black (ON) cell at stage zero.

References

  • S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 170.

Crossrefs

Cf. A246316.

Programs

  • Mathematica
    CAStep[rule_,a_]:=Map[rule[[10-#]]&,ListConvolve[{{0,2,0},{2,1,2},{0,2,0}},a,2],{2}];
    code=324; stages=128;
    rule=IntegerDigits[code,2,10];
    g=2*stages+1; (* Maximum size of grid *)
    a=PadLeft[{{1}},{g,g},0,Floor[{g,g}/2]]; (* Initial ON cell on grid *)
    ca=a;
    ca=Table[ca=CAStep[rule,ca],{n,1,stages+1}];
    PrependTo[ca,a];
    (* Trim full grid to reflect growth by one cell at each stage *)
    k=(Length[ca[[1]]]+1)/2;
    ca=Table[Table[Part[ca[[n]][[j]],Range[k+1-n,k-1+n]],{j,k+1-n,k-1+n}],{n,1,k}];
    on=Map[Function[Apply[Plus,Flatten[#1]]],ca] (* Count ON cells at each stage *)
    Table[Total[Part[on,Range[1,i]]],{i,1,Length[on]}] (* Sum at each stage *)

A271258 First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 324", based on the 5-celled von Neumann neighborhood.

Original entry on oeis.org

3, 1, 7, -4, 16, 1, 15, -7, 11, -4, 48, -11, 23, 21, 55, -39, 27, -23, 63, 13, 71, 21, 75, -31, 51, -3, 107, 5, 51, 37, 123, -23, -29, 57, 95, 25, 115, 17, 187, -39, -5, -11, 155, 73, 83, 73, 147, -19, 39, -11, 203, 13, 147, 21, 219, -35, 95, 13, 219, 41
Offset: 0

Views

Author

Robert Price, Apr 02 2016

Keywords

Comments

Initialized with a single black (ON) cell at stage zero.

References

  • S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 170.

Crossrefs

Cf. A246316.

Programs

  • Mathematica
    CAStep[rule_,a_]:=Map[rule[[10-#]]&,ListConvolve[{{0,2,0},{2,1,2},{0,2,0}},a,2],{2}];
    code=324; stages=128;
    rule=IntegerDigits[code,2,10];
    g=2*stages+1; (* Maximum size of grid *)
    a=PadLeft[{{1}},{g,g},0,Floor[{g,g}/2]]; (* Initial ON cell on grid *)
    ca=a;
    ca=Table[ca=CAStep[rule,ca],{n,1,stages+1}];
    PrependTo[ca,a];
    (* Trim full grid to reflect growth by one cell at each stage *)
    k=(Length[ca[[1]]]+1)/2;
    ca=Table[Table[Part[ca[[n]][[j]],Range[k+1-n,k-1+n]],{j,k+1-n,k-1+n}],{n,1,k}];
    on=Map[Function[Apply[Plus,Flatten[#1]]],ca] (* Count ON cells at each stage *)
    Table[on[[i+1]]-on[[i]],{i,1,Length[on]-1}] (* Difference at each stage *)
Previous Showing 11-15 of 15 results.