|
| |
|
|
A153500
|
|
First 3 terms coincide with A152756. For n>3, a(n) is the palindromic number formed from concatenation of 1, 0, A147759(n-3), 0, A147759(n-3), 0 and 1.
|
|
3
| |
|
|
1, 101, 10001, 1010101, 101101101, 10101010101, 1010010100101, 101010101010101, 10101101010110101, 1010101010101010101, 101010010101010010101, 10101010101010101010101
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
COMMENTS
| a(n) is also A153499(n) written in base 2.
|
|
|
FORMULA
| a(n) = 101*a(n-1)-1110*a(n-2)+102010*a(n-3)-111000*a(n-4)+1010000*a(n-5)-1000000*a(n-6), n>7. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 20 2009]
|
|
|
EXAMPLE
| n ............ a(n)
1 ............. 1
2 ............ 101
3 ........... 10001
4 .......... 1010101
5 ......... 101101101
6 ........ 10101010101
7 ....... 1010010100101
8 ...... 101010101010101
9 ..... 10101101010110101
10 ... 1010101010101010101
======================================
Another visualization of the structure
======================================
1 ............. *
2 ............ /.\
3 ........... /...\
4 .......... /.*.*.\
5 ......... /./|.|\.\
6 ........ /./.|.|.\.\
7 ....... /./..|.|..\.\
8 ...... /./.*.|.|.*.\.\
9 ..... /././|.|.|.|\.\.\
10 ... /././.|.|.|.|.\.\.\
|
|
|
CROSSREFS
| Cf. A135577, A138146, A152576, A152764, A153497, A153498, A153499, A144564.
Sequence in context: A167626 A017764 A152756 * A164367 A094028 A144564
Adjacent sequences: A153497 A153498 A153499 * A153501 A153502 A153503
|
|
|
KEYWORD
| easy,base,nonn
|
|
|
AUTHOR
| Omar E. Pol (info(AT)polprimos.com), Dec 27 2008, Feb 18 2009
|
|
|
EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 20 2009
Keyword:base added by Charles R Greathouse IV (charles.greathouse(AT)case.edu), Apr 26 2010
|
| |
|
|
