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Triangle read by rows, based on the morphism f: 1->2, 2->3, 3->4, 4->5, 5->{5,9,7,6}, 6->7, 7->8, 8->9, 9->10, 10->{10,4,2,1}. 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),...
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%I #6 Mar 12 2014 16:36:47

%S 1,1,2,1,2,2,3,1,2,2,3,2,3,3,4,1,2,2,3,2,3,3,4,2,3,3,4,3,4,4,5,1,2,2,

%T 3,2,3,3,4,2,3,3,4,3,4,4,5,2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,5,9,7,6,1,2,

%U 2,3,2,3,3,4,2,3,3,4,3,4,4,5,2,3,3,4,3,4,4,5,3,4,4,5,4,5,5,5,9,7,6,2,3,3,4

%N Triangle read by rows, based on the morphism f: 1->2, 2->3, 3->4, 4->5, 5->{5,9,7,6}, 6->7, 7->8, 8->9, 9->10, 10->{10,4,2,1}. 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),...

%C A ten-symbol substitution based on a bi-Kenyon-like sign symmetry substitution for the Pisot-Vijayaraghavan constant: x^5-x^3-x-1=0.

%t s[n_] := n /. {1 -> 2, 2 -> 3, 3 -> 4, 4 -> 5, 5 -> {5, 9, 7, 6}, 6 -> 7, 7 -> 8, 8 -> 9, 9 -> 10, 10 -> {10, 4, 2, 1}}; t[a_] := Join[a, Flatten[s /@ a]]; Flatten[ NestList[t, {1}, 6]]

%Y Cf. A105061, A000120, A073058.

%K nonn,tabf

%O 0,3

%A _Roger L. Bagula_, Apr 09 2005

%E Edited by _N. J. A. Sloane_, Jun 16 2007