OFFSET
0,1
COMMENTS
This sequence gives the parenthesis expressions shown at the upper right corner image of the page 103 of NKS, with the left brackets (black squares) converted to 1's and the right brackets (white squares) converted to 0's and then interpreting each such number as a binary number and converted to decimal. A154474 shows the corresponding binary representations. Compare to A080070, A122242, A122245.
LINKS
A. Karttunen and W. Meeussen, Table of n, a(n) for n = 0..100
S. Wolfram, A New Kind of Science, Wolfram Media Inc., (2002), p. 102, p. 103 and pages 104, 896-898.
MATHEMATICA
init=e[e[e][e]][e][e]
toDeca[ w_ ]:=FromDigits[ ToExpression[ Characters[ ToString[ w ] ]/.{"e"->Sequence[], "["->"1", "]"->"0"} ], 2 ]
toDeca /@ NestList[ #/.e[x_ ][y_ ]->x[x[y]]&, init, 100]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Antti Karttunen, with terms a(0)-a(100) also independently computed by Wouter Meeussen, with the given Mathematica program, Jan 11 2009
STATUS
approved