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Odd numbers k for which A006694( (k-1)/2 )< A006694( (A000265(3k+1)-1)/2 ) .
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%I #3 Mar 30 2012 18:52:53

%S 11,23,37,41,43,59,61,79,83,97,103,107,113,121,139,143,147,149,163,

%T 167,169,171,173,177,181,183,191,193,199,201,203,227,237,243,249,251,

%U 263,271,283,287,289,293,303,313,317,321,323,347,351,353,355,359,363,367,373,379

%N Odd numbers k for which A006694( (k-1)/2 )< A006694( (A000265(3k+1)-1)/2 ) .

%C Conjecture: For every k in the sequence, the number k^2 is in the sequence as well.

%C Composite numbers in the sequence which are not perfect squares are 143, 147, 171, 183 etc. [R. J. Mathar, May 16 2009]

%Y A006694, A160198, A122458, A159885, A159945, A160266, A160267.

%K nonn

%O 1,1

%A _Vladimir Shevelev_, May 07 2009

%E Edited and extended by _R. J. Mathar_, May 16 2009