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A110421 Integers with mutual residues -4. 0
5, 9, 41, 1841, 3396641, 11537183669441, 133106607022462246291930241, 17717368833032195779538884761310335951434822778039041 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
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
LINKS
FORMULA
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
MAPLE
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);
CROSSREFS
Sequence in context: A269702 A271016 A176967 * A176751 A123822 A226065
KEYWORD
nonn
AUTHOR
Seppo Mustonen, Sep 11 2005
STATUS
approved

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Last modified June 23 15:01 EDT 2024. Contains 373651 sequences. (Running on oeis4.)