%I A081484
%S A081484 1,3,11,185,21332,462959957,107185713294954842,
%T A081484 11488777233793645715382503248255559,
%U A081484 65996001163867589433635003347899702393519681139860824058982662496745
%N A081484 Consider the mapping f(a/b) = (a^2 + b)/(a^2 - b). Taking a =2, b = 1 
               to start with and carrying out this mapping repeatedly on each new 
               (reduced) rational number gives the following sequence 2/1,5/3,14/
               11,207/185,... Sequence contains the denominators.
%C A081484 The mapping f(a/b) = (a + b)/(a - b). Taking a = 2 b = 1 to start with 
               and carrying out this mapping repeatedly on each new (reduced)rational 
               number gives the periodic sequence 2/1,3/1,2/1,3/1,...
%Y A081484 Cf. A081483.
%Y A081484 Sequence in context: A053888 A118479 A103836 this_sequence A125738 A092840 
               A007156
%Y A081484 Adjacent sequences: A081481 A081482 A081483 this_sequence A081485 A081486 
               A081487
%K A081484 nonn
%O A081484 1,2
%A A081484 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Mar 24 2003
%E A081484 More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 
               06 2003