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%I #14 Feb 23 2015 23:06:27
%S 4,6,8,9,40,42,44,45,46,48,49,60,62,63,64,65,66,68,69,80,81,82,84,85,
%T 86,87,88,90,91,92,93,94,95,96,98,99,400,402,403,404,405,406,407,408,
%U 420,422,423,424,425,426,427,428,429,440,441,442,444,445,446,447,448
%N Right-truncatable composites: every decimal prefix is a composite number.
%C Subsequence of A202259.
%H Stanislav Sykora, <a href="/A202260/b202260.txt">Table of n, a(n) for n = 1..10000</a>
%o (PARI) isComposite(n) = (n>2)&&(!isprime(n));
%o isRightTruncatableComposite(n,b=10) = {my(k=b);if(!isComposite(n),return(0););while(n\k>0,if(!isComposite(n\k),return(0););k*=b);return(1);} \\ _Stanislav Sykora_, Feb 15 2015
%Y Cf. A012883 (right-truncatable noncomposites), A202259 (right-truncatable nonprimes), A024770 (right-truncatable primes).
%Y Cf. A254750, A254752, A254754, A254755 (left-truncatable composites).
%K nonn,base
%O 1,1
%A _Jaroslav Krizek_, Dec 25 2011
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