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A217409
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5-adic valuation of A217407.
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2
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17, 28, 3, 17, 4, 47, 7, 7, 54, 47, 159, 1610
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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A217407=(3^35)*(5^17), so this sequence's first term is 17.
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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, 5), 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,more
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AUTHOR
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STATUS
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approved
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