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A154473 a(n) = A014486(A154472(n)) 4
842, 11090, 13202, 46882, 60994, 231272004, 198873570440, 266349291297936, 64442911458703648, 3667589230123774528, 3336154829743802737792, 17601566387699271821281536, 1023499990310357893964861952 (list; graph; refs; listen; history; text; internal format)
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

Cf. A154475, A154476.

Sequence in context: A158404 A004929 A031736 * A093242 A031527 A252568

Adjacent sequences:  A154470 A154471 A154472 * A154474 A154475 A154476

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

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Last modified May 28 18:24 EDT 2022. Contains 354122 sequences. (Running on oeis4.)