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A217408
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3-adic valuation of A217407.
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2
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35, 20, 59, 42, 63, 5, 69, 73, 21, 43, 71, 1149
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OFFSET
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1,1
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COMMENTS
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See main sequence for rationale.
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LINKS
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EXAMPLE
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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.
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PROG
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(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
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
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CROSSREFS
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KEYWORD
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nonn,base,less
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AUTHOR
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STATUS
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approved
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