%I A124665
%S A124665 20,32,62,84,114,126,134,135,146,150,164,168,176,185,192,196,204,210,
%T A124665 218,232,236,240,248,256,258,282,294,298,305,314,315,324,326,328,342,
%U A124665 348,350,356,366,368,374,375,378,395,406,408,410,414,416,418
%N A124665 Numbers that cannot be either prefixed or followed by one digit to form
a prime.
%C A124665 Prefixing by 0 gives you the number itself. This way it is implicitly
assumed that a(n) is not prime.
%e A124665 If you prefix 20 with any digit you will get an even number. Also 201,
203, 207 and 209 are all composite.
%Y A124665 The sequence A032737 = a(n) cannot be prefixed or followed by any digit
to form a prime - allows you to prefix and postfix at the same time.
%Y A124665 Sequence in context: A116131 A075035 A032352 this_sequence A134989 A119873
A075230
%Y A124665 Adjacent sequences: A124662 A124663 A124664 this_sequence A124666 A124667
A124668
%K A124665 base,nonn
%O A124665 1,1
%A A124665 Tanya Khovanova (tanyakh(AT)yahoo.com), Dec 23 2006
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