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A034174
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a(n) is minimal such that prime factorizations of a(n)-n+1, ..., a(n) have same exponents.
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7
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OFFSET
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1,2
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COMMENTS
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a(8) > 10^13. - Donovan Johnson, Oct 20 2009. [See Reble link for an upper limit.]
The main entry is A034173, which should be updated whenever something relevant is added here. - M. F. Hasler, Oct 28 2012
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LINKS
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FORMULA
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EXAMPLE
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a(4)=19943 because 19940, ..., 19943 all have the form p^2 q r.
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PROG
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(PARI) A034174(n)={my(f); for(k=n, 9e9, f=0; for(i=0, n-1, f==(f=vecsort(factor(k-i)[, 2])) || !i || [k+=n-i-1; next(2)]); return(k))} \\ For illustrative purpose; not useful for n>=6. - M. F. Hasler, Oct 28 2012
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CROSSREFS
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KEYWORD
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hard,nonn,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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