login
This site is supported by donations to The OEIS Foundation.

 

Logo

Many excellent designs for a new banner were submitted. We will use the best of them in rotation.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A126933 Take the decimal number formed by the first n digits of A023396 in reverse order and divide by 2^n. 2
1, 3, 14, 132, 691, 1908, 16579, 47352, 414301, 1183713, 5474669, 27151397, 135646011, 678174568, 6442602909, 18480090517, 85533990571 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The sequence A023396 gives n-digit numbers consisting entirely of 1s and 2s which are divisible by 2^n. The quotients upon division form the present sequence. The parity of the n-th term here determines the next term in A023396; if even, it is a 1 and if odd, a 2.

This was set as a problem in the All Union Mathematical Olympiad of 1971 and can be found in the reference cited here.

REFERENCES

J. B. Tabov and P. J. Taylor, Methods of Problem Solving, Book 1, Australian Mathematics Trust, 1996.

LINKS

Table of n, a(n) for n=1..17.

CROSSREFS

Sequence in context: A186772 A061029 A096657 * A073550 A002966 A075654

Adjacent sequences:  A126930 A126931 A126932 * A126934 A126935 A126936

KEYWORD

nonn,base

AUTHOR

Gerry Leversha (g.leversha(AT)btinternet.com), Mar 18 2007

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified April 18 03:01 EDT 2014. Contains 240688 sequences.