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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.

User: Julien Kluge

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Julien Kluge has authored 1 sequences.

A268312 First number of the periodic part of the "Say what you see" trajectory (see A005151) of n.

Original entry on oeis.org

1031223314, 21322314, 21322314, 21322314, 21322314, 3122331415, 3122331416, 3122331417, 3122331418, 3122331419, 1031223314, 21322314, 21322314, 21322314, 21322314, 3122331415, 3122331416, 3122331417, 3122331418, 3122331419, 10311233, 21322314, 22, 21322314, 31123314, 31123315
Offset: 0

Author

Julien Kluge, Jan 31 2016

Keywords

Comments

a(40) is the first time the periodic part of the trajectory contains more than one term.

Examples

			Consider the starting value n = 5. We see one five: 15. We have one one and one five: 1115. We have three ones and one five: 3115... We reach 3122331415 which produces itself. So a(5) = 3122331415.
		

Crossrefs

A005151 shows a(1) at term number 13.
Cf. A047841.

Programs

  • Mathematica
    a005151[n_, m_] :=
      FromDigits[
       Reverse /@
         Sort[Tally[
           If[n == 2, m, a005151[n - 1, m]] //
            IntegerDigits], #1[[1]] < #2[[1]] &] // Flatten];
    a[n_] := Block[{previousNum = 0, currentNum = 1, knownNums = {n}},
      For[i = 2, currentNum != previousNum, ++i,
       previousNum = currentNum;
       currentNum = a005151[i, n];
       If[MemberQ[knownNums, currentNum], Return[currentNum],
        AppendTo[knownNums, currentNum]];
       ];
      Return[currentNum];
      ]
    a /@ Range[0, 100]