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A217408 3-adic valuation of A217407. 2
35, 20, 59, 42, 63, 5, 69, 73, 21, 43, 71, 1149 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See main sequence for rationale.

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

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.

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, 3), vecsort(Vec(v))) \\ Charles R Greathouse IV, Sep 19 2013

CROSSREFS

Cf. A217407, A217409.

Sequence in context: A088830 A033355 A267402 * A266057 A267341 A174027

Adjacent sequences:  A217405 A217406 A217407 * A217409 A217410 A217411

KEYWORD

nonn,base,less

AUTHOR

James G. Merickel, Oct 02 2012

STATUS

approved

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Last modified January 18 13:38 EST 2022. Contains 350455 sequences. (Running on oeis4.)