Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A141837
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A141837 a(n) = first term that can be reduced in n steps via repeated interpretation of a(n) as a base b+1 number where b is the largest digit of a(n), such that b is always 3 so that each interpretation is base 4. Terms already fully reduced (i.e. single digits) are excluded. +0
7
13, 31, 133, 120332323 (list; graph; listen)
OFFSET

1,1

COMMENT

It is possible to compute additional terms by taking the last term, treating it as base-10 and converting to base-4. This will necessarily create a term which can converted back to base 10 yielding the previous term in the sequence which will itself yield N further terms. But there is no guarantee (except in base 2) that the term so derived will be the first term to produce a sequence of N+1 terms. There could be another, smaller, term which satisfies that requirement but which uses different terms. Pushing the last term of this sequence yields 13023002000203 as a possible next term.

EXAMPLE

a(3) = 133 because 133 is the first number that can produce a sequence of three terms by repeated interpetation as a base 4 number: [133] (base-4) --> [31] (base-4) --> [13] (base-4) --> [7]. Since 7 cannot be interpretted as a base 4 number, the sequence terminates with 13. a(1) = 13 because 13 is the first number that can be reduced once, yielding no further terms interprettable as base 4.

CROSSREFS

Cf. A091049, A141836, A141838, A141839, A141840, A141841, A141842.

Adjacent sequences: A141834 A141835 A141836 this_sequence A141838 A141839 A141840

Sequence in context: A043226 A044006 A007628 this_sequence A104151 A023304 A087511

KEYWORD

base,more,nonn

AUTHOR

Chuck Seggelin (seqfan(AT)plastereddragon.com), Jul 10 2008

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 8 20:39 EST 2009. Contains 166234 sequences.


AT&T Labs Research