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A361228
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a(n) is the first number k such that k + a(i) has n prime factors, counted with multiplicity, for all i < n; a(0) = 0.
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1
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OFFSET
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0,2
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COMMENTS
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a(8) > 3*10^9 if it exists.
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LINKS
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FORMULA
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A001222(a(i) + a(j)) = j for 0 <= i < j.
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EXAMPLE
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a(3) = 66 because a(0) + 66 = 66 = 2*3*11, a(1) + 66 = 68 = 2*2*17, and a(2) + 66 = 70 = 2*5*7 all have 3 prime factors, counted with multiplicity, and 66 is the least number that works.
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MAPLE
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A:= [0]:
for i from 1 to 7 do
for x from 2^i do if andmap(t -> numtheory:-bigomega(t+x) = i, A) then
A:= [op(A), x]; break
fi od od:
A;
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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