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A074811
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Least k such that prime(k) >= k*tau(k*n) where tau = A000005.
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0
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1, 1, 1, 181, 1, 1061, 1, 1061, 181, 1061, 1, 40123, 1, 1061, 1061, 6473, 1, 40123, 1, 40123, 1061, 1061, 1, 1617211, 181, 1061, 1061, 40123, 1, 1617211, 1, 40123, 1061, 1061, 1061, 10553429, 1, 1061, 1061, 1617211, 1, 1617211, 1, 40123, 40123, 1061, 1, 69709687
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OFFSET
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1,4
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COMMENTS
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Listed terms are = 1 or are primes.
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LINKS
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PROG
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(PARI) a(n)=if(n<0, 0, my(s=1); while(prime(s)<s*numdiv(s*n), s++); s)
(PARI) a(n)= my(k=1, p=2); while(p<k*numdiv(k*n), k++; p=nextprime(p+1)); k; \\ Michel Marcus, Apr 05 2020
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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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