%I A138336
%S A138336 18,27,127,1111
%N A138336 First occurence of exactly n consecutive numbers after A138335(n) (A138335(n) 
               excluded).
%C A138336 Such number digits after decimal point of number Pi where the approximation 
               to the number Pi by a root of a polynomial of 2 degree does not improve 
               the accuracy exactly n next digits
%e A138336 a(1)=18 because 3.141592653589793238 (18 digits) is root of -3061495+674903*x+95366*x^2 
               and 3.1415926535897932385 (19 digits) also is root of that same polynomial 
               -3061495+674903*x+95366*x^2
%Y A138336 Cf. A138335, A138337, A138338.
%Y A138336 Sequence in context: A109911 A065751 A038632 this_sequence A166630 A154920 
               A094224
%Y A138336 Adjacent sequences: A138333 A138334 A138335 this_sequence A138337 A138338 
               A138339
%K A138336 nonn,uned,probation
%O A138336 1,1
%A A138336 Artur Jasinski (grafix(AT)csl.pl), Mar 15 2008
%E A138336 There are comments in the entry for A138335 which may cast doubt on the 
               validity of this and related sequences. - N. J. A. Sloane (njas(AT)research.att.com), 
               Mar 19 2008