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A110389
Integers with mutual residues -1.
0
2, 3, 5, 29, 869, 756029, 571580604869, 326704387862983487112029, 106735757048926752040856495274871386126283608869, 11392521832807516835658052968328096177131218666695418950023483907701862019030266123104859068029
OFFSET
1,1
COMMENTS
This is the special case k=1 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.
Same as A005267 but with the first two terms in reverse order.
FORMULA
a(1)=2, a(2)=3, a(n) = -1 + a(1)*a(2)*...*a(n-1);
a(n) = a(n-1)^2 + a(n-1) - 1, 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(1, n), n=1..10);
MATHEMATICA
Join[{2, 3}, NestList[#^2+#-1&, 5, 10]] (* Harvey P. Dale, Jul 13 2015 *)
CROSSREFS
Cf. A000289.
Sequence in context: A093490 A073309 A226124 * A083388 A090475 A060301
KEYWORD
nonn
AUTHOR
Seppo Mustonen, Sep 11 2005
EXTENSIONS
One more term (a(10)) from Harvey P. Dale, Jul 13 2015
STATUS
approved