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A181488
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Composite Flavius' numbers (A000960) whose divisors are again Flavius' numbers.
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2
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39, 49, 91, 133, 763, 15883, 21207, 32761, 180739, 268423, 746607, 2277163, 28604419, 93742347, 13192600483, 124387470307, 3898087261291, 13987912482103, 69089500671469
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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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PROG
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(PARI) A181488(Nmax) = { my(S=[]); for(n=1, Nmax, my(F=n); for(i=1, n-1, F=(n-i)*ceil(F/(n-i)+1)); S=setunion(S, Set(F)); isprime(F) & next; fordiv(F, d, setsearch(S, d)|next(2)); print1(F", "))}
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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