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%I #8 Feb 15 2017 00:54:45
%S 75,99,117,153,171,175,195,333,357,399,531,539,555,595,711,715,775,
%T 777,795,931,935,1113,1179,1331,1359,1519,1533,1557,1573,1719,1737,
%U 1773,1775,1791,1975,3171,3177,3179,3357,3395,3515,3553,3573,3577,3751,3757,3759
%N Odd-digit products of three odd-digit primes p*q*r.
%C Odd-digit primes p,q,r are not necessarily all different, e.g. 75=3*5*5, 99=3*3*11, 1533=3*7*73, etc. Cf. A107076: Odd-digit semiprimes divisors of which are odd-digit primes.
%H Charles R Greathouse IV, <a href="/A107077/b107077.txt">Table of n, a(n) for n = 1..10000</a>
%t With[{odps=Select[Prime[Range[100]],And@@OddQ[IntegerDigits[#]]&]}, Union[Select[Times@@@Tuples[odps,3],And@@OddQ[IntegerDigits[#]]&]]] (* _Harvey P. Dale_, Feb 02 2012 *)
%o (PARI) D=[0,2,4,6,8];
%o oddDigits(n)=#setintersect(Set(digits(n)),D)==0
%o list(lim)=my(v=List(),P=v,L=lim\3,pq,t); forprime(p=3,L\3, if(oddDigits(p), listput(P,p))); P=Vec(P); for(i=1,#P, for(j=1,i, pq=P[i]*P[j]; if(pq>L, break); for(k=1,j, t=pq*P[k]; if(t>lim, break); if(oddDigits(t), listput(v, t))))); P=0; Set(v) \\ _Charles R Greathouse IV_, Feb 15 2017
%Y Cf. A107076.
%K nonn,base
%O 1,1
%A _Zak Seidov_, May 10 2005
%E Corrected and extended by Harvey P. Dale, Feb 02 2012
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