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Integers with mutual residues -9.
0

%I #3 Mar 30 2012 18:59:35

%S 10,19,181,34381,1182362581,1397981283590244781,

%T 1954351669268628414383088499809940981,

%U 3819490447173074341052986454970501004004783894423555148483555928992711181

%N Integers with mutual residues -9.

%C This is the special case k=9 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}.

%C An infinite coprime sequence

%H S. Mustonen, <a href="http://www.survo.fi/papers/resseq.pdf">On integer sequences with mutual k-residues</a>

%F a(1)=10, a(2)=19, a(n)=a(1)*a(2)*...*a(n-1) - 9.

%F a(n)=a(n)^2+9*a(n)-9, n>3

%p 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(9,n),n=1..8);

%K nonn

%O 1,1

%A _Seppo Mustonen_, Sep 11 2005