A105105 Triangle read by rows, based on the morphism f: 1-> 2->3 3->{6,5,4} 4->5 5->6 6->{3,2,1}. First row is 1. If current row is a,b,c,..., then the next row is a,b,c,...,f(a),f(b),f(c),...
1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 6, 5, 4, 1, 2, 2, 3, 2, 3, 3, 6, 5, 4, 2, 3, 3, 6, 5, 4, 3, 6, 5, 4, 6, 5, 4, 3, 2, 1, 6, 5, 1, 2, 2, 3, 2, 3, 3, 6, 5, 4, 2, 3, 3, 6, 5, 4, 3, 6, 5, 4, 6, 5, 4, 3, 2, 1, 6, 5, 2, 3, 3, 6, 5, 4, 3, 6, 5, 4, 6, 5, 4, 3, 2, 1, 6, 5, 3, 6, 5, 4, 6, 5, 4, 3, 2, 1, 6, 5, 6, 5
Offset: 0
Examples
Triangle begins: 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 6, 5, 4, 1, 2, 2, 3, 2, 3, 3, 6, 5, 4, 2, 3, 3, 6, 5, 4, 3, 6, 5, 4, 6, 5, 4, 3, 2, 1, 6, 5, ...
Links
- Richard Kenyon, The Construction of Self-Similar Tilings
Crossrefs
Cf. A103684.
Programs
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Mathematica
s[n_] := n /. {1 -> 2, 2 -> 3, 3 -> {6, 5, 4}, 4 -> 5, 5 -> 6, 6 -> {3, 2, 1}}; t[a_] := Join[a, Flatten[s /@ a]]; Flatten[ NestList[t, {1}, 5]] NestList[ Flatten[ Join[ #, # /. {1 -> {2}, 2 ->{3}, 3 ->{6,5,4}, 4 ->{5}, 5-> {6}, 6-> {3,2,1}} ]] &, {1}, 5] // Flatten (* Robert G. Wilson v, Jun 05 2014 *)
Comments