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%I #9 Mar 01 2014 05:13:33
%S 1,9,27,39,49,51,57,63,81,91,93,99,33,69,77,21,87,117,123,129,153,171,
%T 187,201,213,217,231,237,249,259,279,289,291,297,301,303,319,321,327,
%U 361,381,399,423,427,429,447,451,453,459,471,481,483,489,493,511
%N The nonprime numbers formed from the primes in A238332.
%H T. D. Noe, <a href="/A238333/b238333.txt">Table of n, a(n) for n = 1..2700</a>
%t t = {}; eList = {}; p = 7; While[Length[t] < 1000, p = NextPrime[p]; e = FromDigits[Rest[IntegerDigits[p]]]; If[! PrimeQ[e] && ! MemberQ[eList, e], AppendTo[t, p]; AppendTo[eList, e]]]; eList
%o (Haskell)
%o a238333 n = a238333_list !! (n-1)
%o a238333_list = f [] $ drop 4 a000040_list where
%o f xs (p:ps) | a010051 t == 1 || t `elem` xs = f xs ps
%o | otherwise = t : f (t:xs) ps
%o where t = read $ tail $ show p
%o -- _Reinhard Zumkeller_, Feb 28 2014
%Y Cf. A000040 (prime numbers), A238332.
%Y Cf. A010051.
%K nonn,base
%O 1,2
%A _T. D. Noe_, Feb 28 2014
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