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.

A339122 Number of elements of the Rubik's Cube group of order A338883(n).

Original entry on oeis.org

1, 170911549183, 33894540622394, 4346957030144256, 133528172514624, 140621059298755526, 153245517148800, 294998638981939200, 55333752398428896, 34178553690432192, 44590694400, 2330232827455554048, 23298374383021440, 14385471333209856, 150731886270873600
Offset: 1

Views

Author

Ben Whitmore, Nov 24 2020

Keywords

Comments

The most common order is 60, with a(33) = 4199961633799421952 elements, or about 9.71% of the group.
The least common order (excluding 1) is 11, with a(11) = 44590694400 elements, or about 0.0000001% of the group. Elements of order 11 are rare because they cannot affect the corner pieces of the cube.

Examples

			a(1) = 1 because the only element of order A338883(1) = 1 is the identity element.
a(73) = 51490480088678400 is the number of elements of order A338883(73) = 1260.
		

Crossrefs

Programs

  • Mathematica
    pN[p_] := Total[p]!/Times@@p/Times@@Factorial[Flatten[Tally[p]][[2 ;; ;; 2]]]
    oddQ[p_] := OddQ[Total[p - 1]]
    ord[p_] := LCM @@ p
    oriN[p_, o_] := Module[{i, t, a = 0, ns = 0, s = 0, r}, t = ord[p]/p;
      For[i = 1, i <= Length[p], i++,
       If[Mod[t[[i]], o] == 0, a += p[[i]], ns += 1; s += p[[i]]]];
         {If[a == 0, r = o^(s - ns), r = o^a o^(s - ns - 1)], o^(a + s - 1) - r}]
    val[p1_, o1_, p2_, o2_] :=
    Module[{z}, z = pN[p1] pN[p2];
         {{LCM[ord[p1], ord[p2]],z oriN[p1, o1][[1]] oriN[p2, o2][[1]]},
         {{LCM[ord[p1] o1,ord[p2]],z oriN[p1, o1][[2]] oriN[p2, o2][[1]]}},   {{LCM[ord[p1],ord[p2] o2],z oriN[p1, o1][[1]] oriN[p2, o2][[2]]}},
      {{LCM[ord[p1] o1, ord[p2] o2], z oriN[p1, o1][[2]] oriN[p2, o2][[2]] }}}]
    p8 = IntegerPartitions[8]; p12 = IntegerPartitions[12];
    ce = Select[p8, ! oddQ[#] &]; co = Select[p8, oddQ[#] &];
    ee = Select[p12, ! oddQ[#] &]; eo = Select[p12, oddQ[#] &];
    res = {}; max = 0;
    For[i = 1, i <= Length[ce], i++,
    For[j = 1, j <= Length[ee], j++,
      AppendTo[res, val[ce[[i]], 3, ee[[j]], 2]]]]
    For[i = 1, i <= Length[co], i++,
    For[j = 1, j <= Length[eo], j++,
      AppendTo[res, val[co[[i]], 3, eo[[j]], 2]]]]
    p = Partition[res // Flatten, 2]; c // Clear;
    For[i = 1, i <= Length[p], i++,
      If [IntegerQ[c[p[[i, 1]]]], c[p[[i, 1]]] += p[[i, 2]],
       c[p[[i, 1]]] = p[[i, 2]]]; If[p[[i, 1]] > max, max = p[[i, 1]]]];
    Select[Table[c[i], {i, 1, max}], IntegerQ[#] &] (* Herbert Kociemba, Jun 30 2022 *)
  • Python
    # See post #11 in SpeedSolving Puzzles Community link.

Formula

Sum_{n=1..73} a(n) = 43252003274489856000 = A075152(3).

Extensions

a(10) corrected by Ben Whitmore, Jun 27 2022