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%I #12 Mar 30 2012 17:39:47
%S 1,111,10101,1001001,101010101,10110101101,1010101010101,
%T 101001010100101,10101010101010101,1010110101010110101,
%U 101010101010101010101,10101001010101010010101
%N Palindromes formed from concatenation of A147759(n) and the same string A147759(n) but without its initial digit.
%C a(n) is also A153497(n) written in base 2.
%F 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). G.f.: x(1+10x+2000x^3-91000*x^4+100000x^5)/((1-100x)(1-x)(1+10x^2)(1+1000x^2)). [From _R. J. Mathar_, Feb 20 2009]
%e n ............. a(n)
%e 1 .............. 1
%e 2 ............. 111
%e 3 ............ 10101
%e 4 ........... 1001001
%e 5 .......... 101010101
%e 6 ......... 10110101101
%e 7 ........ 1010101010101
%e 8 ....... 101001010100101
%e 9 ...... 10101010101010101
%e 10 .... 1010110101010110101
%e 11 ... 101010101010101010101
%e ======================================
%e Another visualization of the structure
%e ======================================
%e 1 .............. *
%e 2 ............. /|\
%e 3 ............ /.|.\
%e 4 ........... /..|..\
%e 5 .......... /.*.|.*.\
%e 6 ......... /./|.|.|\.\
%e 7 ........ /./.|.|.|.\.\
%e 8 ....... /./..|.|.|..\.\
%e 9 ...... /./.*.|.|.|.*.\.\
%e 10 .... /././|.|.|.|.|\.\.\
%e 11 ... /././.|.|.|.|.|.\.\.\
%Y Cf. A135577, A138146, A152576, A152764, A153497, A153499, A153500, A144564.
%K easy,base,nonn
%O 1,2
%A _Omar E. Pol_, Dec 27 2008, Feb 18 2009
%E More terms from _R. J. Mathar_, Feb 20 2009
%E Keyword:base added by _Charles R Greathouse IV_, Apr 23 2010
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