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A110421
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Integers with mutual residues -4.
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0
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OFFSET
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1,1
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COMMENTS
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This is the special case k=4 of sequences with mutual residues -k. In general, a(1)=k+1 and a(n)=min{m | m>a(n-1), mod(m,a(i))=-k, i=1,...,n-1}.
An infinite coprime sequence
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LINKS
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FORMULA
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a(1)=5, a(2)=9, a(n)=-1+a(1)*a(2)*...*a(n-1)
a(n)=a(n)^2+4*a(n)-4, n>3
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MAPLE
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a:=proc(k, n::nonnegint) option remember; if n<3 then RETURN(n*k+1); fi; if n=3 then RETURN(a(k, 1)*a(k, 2)-k); fi; a(k, n-1)*(a(k, n-1)+k)-k; end; seq(a(4, n), n=1..9);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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