Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A154473
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A154473 a(n) = A014486(A154472(n)) +0
4
842, 11090, 13202, 46882, 60994, 231272004, 198873570440, 266349291297936, 64442911458703648, 3667589230123774528, 3336154829743802737792, 17601566387699271821281536, 1023499990310357893964861952 (list; graph; listen)
OFFSET

0,1

COMMENT

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: A004929 A031736 A031617 this_sequence A093242 A031527 A045243

Adjacent sequences: A154470 A154471 A154472 this_sequence A154474 A154475 A154476

KEYWORD

nonn,base

AUTHOR

Antti Karttunen (His-Firstname.His-Surname(AT)gmail.com), with terms a(0)-a(100) also independently computed by Wouter Meeussen (wouter.meeussen(AT)pandora.be), with the given Mathematica program, Jan 11 2009

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 23 10:40 EST 2009. Contains 167421 sequences.


AT&T Labs Research