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%I #8 Mar 06 2016 04:34:24
%S 1,3,4,7,8,12,13,16,17,20,21,24,25,28,29,32,33,36,37,40,43,44,47,48,
%T 52,55,56,59,60,63,64,67,68,71,72,75,76,79,80,83,84,87,88,91,92,95,96,
%U 99,100,103,104,107,108,111,112,115,116,119,120
%N a(n) = least positive integer > a(n-1) and not a(i)*a(j)+2 for i<=1<=j<=n, n >= 2/.
%H Ivan Neretin, <a href="/A026449/b026449.txt">Table of n, a(n) for n = 1..1000</a>
%t a = {1, 3}; used = {a[[1]]^2 + 2, a[[1]]*a[[2]] + 2, a[[2]]^2 + 2}; Do[k = a[[-1]] + 1; While[MemberQ[used, k], k++]; AppendTo[a, k]; used = Union[used, k*a + 2], {n, 3, 60}]; a (* _Ivan Neretin_, Mar 06 2016 *)
%Y Cf. A026443 and references therein.
%K nonn
%O 1,2
%A _Clark Kimberling_