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A217409
5-adic valuation of A217407.
2
17, 28, 3, 17, 4, 47, 7, 7, 54, 47, 159, 1610
OFFSET
1,1
COMMENTS
See main sequence, A217407.
EXAMPLE
A217407=(3^35)*(5^17), so this sequence's first term is 17.
PROG
(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
CROSSREFS
Sequence in context: A146776 A147218 A146856 * A256361 A293927 A269307
KEYWORD
nonn,base,more
AUTHOR
James G. Merickel, Oct 02 2012
STATUS
approved