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%I #5 Nov 02 2014 18:39:41
%S 3,6,7,11,14,15,19,21,22,23,30,31,33,34,35,38,39,42,43,46,47,51,55,57,
%T 59,62,66,67,69,70,71,77,78,79,83,86,87,91,93,94,95,102,103,105,107,
%U 110,111,114,115,118,119,123,127,129,131,133,134,138,139,141,142,143,146
%N Sequence of squarefree n such that Q(sqrt(n)) has no element with a fully periodical continued fraction of period 1.
%C Diophantine equation x^2 - n.y^2 + 4 = 0 has no solution (x,y) for a given squarefree n. Squarefree n not in the sequence A013946. Same sequence with square factors allowed is A087643.
%e 3 is in the sequence because no [k,k,k,k,...] is in Q(sqrt(3))
%e 5 is not in the sequence since Q(sqrt(5)) contains [1,1,1,1,...]
%Y Cf. A087643, A013946.
%K easy,nonn
%O 3,1
%A _Thomas Baruchel_, Sep 16 2003