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A026446 a(n) = least positive integer > a(n-1) and not a(i)*a(j)+2 for 1<=i<j<=n. 2

%I #8 Mar 06 2016 03:57:57

%S 2,4,5,6,7,8,9,11,13,15,17,19,21,23,25,27,29,31,33,35,39,41,43,45,49,

%T 51,53,55,59,61,63,66,69,71,73,75,76,81,82,83,85,89,91,95,96,98,99,

%U 103,105,109,111,113,114,115,123,125,129,130,131

%N a(n) = least positive integer > a(n-1) and not a(i)*a(j)+2 for 1<=i<j<=n.

%H Ivan Neretin, <a href="/A026446/b026446.txt">Table of n, a(n) for n = 1..1000</a>

%t a = {2, 4}; used = {a[[1]]*a[[2]] + 2}; Do[k = a[[-1]] + 1; While[MemberQ[used, k], k++]; used = Union[used, k*a + 2]; AppendTo[a, k], {n, 3, 60}]; a (* _Ivan Neretin_, Mar 06 2016 *)

%Y Cf. A026443 and references therein.

%K nonn

%O 1,1

%A _Clark Kimberling_

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