A105164 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),...

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, 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, 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

Offset

0,3

Comments

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.

Links

Table of n, a(n) for n=0..104.

Mathematica

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]]

Crossrefs

Cf. A105061, A000120, A073058.

Sequence in context: A207328 A105056 A105061 * A000120 A105062 A106487

Adjacent sequences: A105161 A105162 A105163 * A105165 A105166 A105167

Keyword

nonn,tabf

Author

Roger L. Bagula, Apr 09 2005

Extensions

Edited by N. J. A. Sloane, Jun 16 2007

Status

approved