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%I #4 Mar 30 2012 17:26:10
%S 1,2,3,1,2,4,1,2,1,1,2,2,1,1,6,1,2,3,1,2,1,1,2,1,1,2,2,1,1,3,1,2,3,1,
%T 1,4,1,2,1,1,2,1,1,1,2,1,2,3,1,2,4,1,2,1,1,1,1,1,1,2,1,2,1,1,2,3,1,1,
%U 1,1,2,2,1,1,7,1,1,2,1,2,1,1,2,1,1,2,2,1,1,1,1,2,3,1,2,2,1,1,1,1,1,2,1,1,1
%N Number of primes in arithmetic progression starting with 7 and with d=2n.
%C Arithmetic progression is stopped when next term is not prime. E.g. for n=3, a=3, that is 7,13,19 are prime, while next term, 25, is not prime.
%t bb={}; Do[s=1; Do[If[PrimeQ[7+k*d], s=s+1, bb={bb, s}; Break[]], {k, 10}], {d, 2, 200, 2}]; Flatten[bb]
%Y Cf. A088420, A088421, A088423, A088424, A088425, A088426, A088427, A088428, A088429.
%K easy,nonn
%O 1,2
%A _Zak Seidov_, Sep 29 2003