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%I #5 Jun 18 2021 15:25:46
%S 4,7,13,19,33,35,36,43,48,55,59,62,87,129,149,153,159,190,228,231,245,
%T 265,266,269,284,300,329,331,340,347,372,432,449,450,461,485,496,500,
%U 514,544,560,565,594,598,605,614,639,677,684,734,736,794,804,813,882
%N a(n) is the smallest positive integer m such that b * (Product_{k=1..n} a(k)) + 1 is prime, with b = 7.
%t k = 7; a = {}; Do[If[PrimeQ[k n + 1], k = k n; AppendTo[a, n]], {n, 1, 3000}]; a (*Artur Jasinski*)
%Y A046966, A046972, A144717, A144718, A144722, A144723, A144724, A144725, A144726, A144727, A144728, A144729, A144731
%K nonn
%O 1,1
%A _Artur Jasinski_, Sep 19 2008
%E Definition corrected by _Georg Fischer_, Jun 18 2021