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A235397
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The first term of the least sequence of n consecutive Moran numbers.
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4
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OFFSET
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1,1
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COMMENTS
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A number n is a Moran number if n divided by the sum of its decimal digits is prime.
Jens Kruse Andersen found that a(7) <= 2196125475223740 and a(8) <= 905295493763807066010 (see Rivera link).
Since Moran numbers (A001101) are also Niven numbers (A005349), this sequence is finite with no more than 20 terms (see A060159). (End)
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LINKS
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EXAMPLE
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a(6) = 4007565001480 because
4007565001480 = 40 * 100189125037,
4007565001481 = 41 * 97745487841,
4007565001482 = 42 * 95418214321,
4007565001483 = 43 * 93199186081,
4007565001484 = 44 * 91081022761,
4007565001485 = 45 * 89057000033.
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PROG
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(PARI) isA001101(n)=(k->denominator(k)==1&&isprime(k))(n/sumdigits(n))
a(n)=my(k=n); while(1, forstep(i=k, k-n+1, -1, if(!isA001101(i), k=i+n; next(2))); return(k-n+1)) \\ Charles R Greathouse IV, Jan 10 2014
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CROSSREFS
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KEYWORD
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nonn,hard,base,fini,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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