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%I #10 Apr 29 2014 22:49:29
%S 10,14,15,21,25,26,34,35,38,39,46,49,51,57,58,62,65,69,74,82,85,86,87,
%T 91,93,94,95,115,118,119,121,122,133,141,155,161,166,177,202,221,226,
%U 262,299,303,323,334,335,339,355,377,393,411,422,445,446,447,454
%N Semiprimes which have one or more occurrences of exactly two different digits.
%C The first term having a repeated digit is 115.
%e 1000000000010101 is a term because it is made of the digits 0 and 1 and it is the product of the two primes 18463559 and 54160739.
%t Select[Range[454], Length@Union@ IntegerDigits[#] == 2 && Total[Last /@ FactorInteger[#]] == 2 &] (* _Giovanni Resta_, Jan 14 2014 *)
%o (PARI)
%o list(lim)=my(v=List(), t); forprime(p=2, sqrt(lim), t=p; forprime(q=p, lim\t, listput(v, t*q))); vecsort(Vec(v)) \\ From A001358
%o b=list(10000); s=[]; for(n=1, #b, if(#vecsort(eval(Vec(Str(b[n]))),,8)==2, s=concat(s, b[n]))); s
%Y Cf. A235691-A235696.
%Y Cf. A235154-A235161.
%K nonn,base
%O 1,1
%A _Colin Barker_, Jan 14 2014
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