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A046387
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Products of exactly 5 distinct primes.
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35
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2310, 2730, 3570, 3990, 4290, 4830, 5610, 6006, 6090, 6270, 6510, 6630, 7410, 7590, 7770, 7854, 8610, 8778, 8970, 9030, 9282, 9570, 9690, 9870, 10010, 10230, 10374, 10626, 11130, 11310, 11730, 12090, 12210, 12390, 12558, 12810, 13090, 13110
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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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EXAMPLE
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a(1) = 2310 = 2 * 3 * 5 * 7 * 11 = A002110(5) = 5#.
a(2) = 2730 = 2 * 3 * 5 * 7 * 13.
a(3) = 3570 = 2 * 3 * 5 * 7 * 17.
a(10) = 6006 = 2 * 3 * 7 * 11 * 13.
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MAPLE
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option remember;
local a;
if n = 1 then
2*3*5*7*11 ;
else
for a from procname(n-1)+1 do
if A001221(a)= 5 and issqrfree(a) then
return a;
end if;
end do:
end if;
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MATHEMATICA
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PROG
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(PARI) is(n)= omega(n)==5 && bigomega(n)==5 \\ Hugo Pfoertner, Dec 18 2018
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CROSSREFS
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Cf. A000040, A000961, A001221, A005117, A000977, A002110, A006881, A007304, A007774, A033992, A033993, A046386.
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KEYWORD
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easy,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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