%I #3 Mar 30 2012 17:30:32
%S 407,1189,1343,1681,7597,8791,10579,16147,23479,24341,25751,26101,
%T 28757,34093,36349,39961,47053,47669,52891,58879,62263,64277,79223,
%U 88183,93829,96029,98261
%N Composite numbers not divisible by 2 which in base 4 contain their largest proper factor as a substring.
%t Do[ If[ !PrimeQ[ n ] && StringPosition[ ToString[ FromDigits[ IntegerDigits[ n, 4 ] ] ], ToString[ FromDigits[ IntegerDigits[ Divisors[ n ][ [ -2 ] ], 4 ] ] ] ] != {}, Print[ n ] ], {n, 3, 10^5, 2} ]
%Y Cf. A062238.
%K base,nonn
%O 1,1
%A _Robert G. Wilson v_, Aug 08 2001
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