%I A086383
%S A086383 2,5,29,5741,33461,44560482149,1746860020068409,68480406462161287469,
%T A086383 13558774610046711780701,4125636888562548868221559797461449,
%U A086383 4760981394323203445293052612223893281
%N A086383 Primes found among the denominators of the continued fraction rational 
               approximations to sqrt(2).
%t A086383 Select[Table[ChebyshevU[k,3]-ChebyshevU[k-1,3],{k,0,50}],PrimeQ] - Ed 
               Pegg Jr (ed(AT)mathpuzzle.com), May 10 2007
%o A086383 (PARI) \Continued fraction rational approximation of numeric constants 
               f. m=steps. cfracdenomprime(m,f) = { default(realprecision,3000); 
               cf = vector(m+10); x=f; for(n=0,m, i=floor(x); x=1/(x-i); cf[n+1] 
               = i; ); for(m1=0,m, r=cf[m1+1]; forstep(n=m1,1,-1, r = 1/r; r+=cf[n]; 
               ); numer=numerator(r); denom=denominator(r); if(ispseudoprime(denom),
               print1(denom,",")); ) }
%Y A086383 Cf. A056869. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 12 
               2008]
%Y A086383 Sequence in context: A000283 A121910 A073833 this_sequence A118612 A158866 
               A101078
%Y A086383 Adjacent sequences: A086380 A086381 A086382 this_sequence A086384 A086385 
               A086386
%K A086383 nonn
%O A086383 1,1
%A A086383 Cino Hilliard (hillcino368(AT)gmail.com), Sep 06 2003; corrected Jul 
               30 2004