Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A030302
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A030302 Write n in base 2 and juxtapose. +0
8
1, 1, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 1, 1, 1 (list; graph; listen)
OFFSET

1,1

FORMULA

Let "index" i = ceiling( W(log(2)/2 (n - 1))/log(2) + 1 ) where W denotes the principal branch of the Lambert W function. Then a(n) = mod(floor(2^(mod(n + 2^i - 2, i) - i + 1) ceiling((n + 2^i - 1)/i - 1)), 2). See also Mathematica code. - David W. Cantrell (DWCantrell(AT)sigmaxi.net), Feb 19 2007

MATHEMATICA

i[n_] := Ceiling[FullSimplify[ProductLog[Log[2]/2 (n - 1)]/Log[2] + 1]]; a[n_] := Mod[Floor[2^(Mod[n + 2^i[n] - 2, i[n]] - i[n] + 1) Ceiling[(n + 2^i[n] - 1)/i[n] - 1]], 2]; - David W. Cantrell (DWCantrell(AT)sigmaxi.net), Feb 19 2007

CROSSREFS

Essentially same as A030190. Cf. A030303, ...

Sequence in context: A014114 A014219 A065828 this_sequence A051023 A030657 A076213

Adjacent sequences: A030299 A030300 A030301 this_sequence A030303 A030304 A030305

KEYWORD

nonn,base

AUTHOR

Clark Kimberling (ck6(AT)evansville.edu)

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 July 26 13:41 EDT 2008. Contains 142293 sequences.


AT&T Labs Research