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%I #11 Sep 07 2014 08:34:31
%S 35,20,59,42,63,5,69,73,21,43,71,1149
%N 3-adic valuation of A217407.
%C See main sequence for rationale.
%e The first number that has only 3 and 5 as prime factors and has prime counts of each digit 0-9 in its decimal representation is (3^35)*(5^17), so, corresponding to that being A217407(1), this sequence's first term is 35.
%o (PARI) prDigits(n)=my(d=digits(n), v=vector(10)); for(i=1, #d, v[d[i]+1]++); for(i=1, 10, if(!isprime(v[i]), return(0))); 1
%o list(lim)=my(v=List(), t); for(a=0, log(lim+.5)\log(5), t=5^a; while(t<=lim, if(prDigits(t), listput(v, t)); t*=3)); apply(k -> valuation(k,3), vecsort(Vec(v))) \\ _Charles R Greathouse IV_, Sep 19 2013
%Y Cf. A217407, A217409.
%K nonn,base,less
%O 1,1
%A _James G. Merickel_, Oct 02 2012