%I A044567
%S A044567 48,97,146,195,244,293,342,391,440,489,538,587,636,685,734,783,832,881,
%T A044567 930,979,1028,1077,1126,1175,1224,1273,1322,1371,1420,1469,1518,1567,
%U A044567 1616,1665,1714,1763,1812,1861,1910,1959,2008
%N A044567 Numbers n such that string 6,6 occurs in the base 7 representation of 
               n but not of n+1.
%C A044567 If A=[A157362] 49*n.^2-2*n (n>0, 47, 192, 435,.,. ,.,); Y=[A010727] 7 
               (7,7,7,.,.,); X=[A044567] 49*n-1 (n>0, 48, 97, 146, ,. .,), we have, 
               for all terms, Pell's equation X^2-A*Y^2=1. Example: 48^2-47*7^2=1; 
               97^2-192*7^2=1; 146^2-435*7^2=1. [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), 
               Mar 12 2009]
%H A044567 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/
               NonRecursions.html">Non Recursions</a>
%F A044567 a(n)=49*n-1 (n>0) [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), 
               Mar 12 2009]
%e A044567 For n=1, a(1)=48; n=2, a(2)=97; n=3, a(3)=146 [From Vincenzo Librandi 
               (vincenzo.librandi(AT)tin.it), Mar 12 2009]
%Y A044567 Cf. A157362, A010727 [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it), 
               Mar 12 2009]
%Y A044567 Sequence in context: A043418 A031486 A044186 this_sequence A070258 A113797 
               A044235
%Y A044567 Adjacent sequences: A044564 A044565 A044566 this_sequence A044568 A044569 
               A044570
%K A044567 nonn,base
%O A044567 1,1
%A A044567 Clark Kimberling (ck6(AT)evansville.edu)