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a(n) = position of A045392(n) in A042997.
0

%I #2 Mar 30 2012 17:26:35

%S 1,8,10,18,24,29,32,37,43,56,57,61,63,67,73,74,79,84,87,100,105,110,

%T 118,125,126,130,134,143,150,157,160,165,175,177,184,185,187,188,193,

%U 200,205,215,230,233,235,242,248,256,258,261,262,265,272,276,278,279,290

%N a(n) = position of A045392(n) in A042997.

%C Positions of primes congruent to {2} mod 7 among primes congruent to {2,3,4,5,6} mod 7.

%t pr=Prime[Range[500]];A042997=Select[pr,1<Mod[ #,7]&];

%t A045392=Select[A042997,2==Mod[ #,7]&];

%t s=Flatten[Position[A042997,# ]&/@A045392]

%Y Cf. A042997 Primes congruent to {2, 3, 4, 5, 6} mod 7, A045392 Primes congruent to {2} mod 7.

%K nonn

%O 1,2

%A _Zak Seidov_, Jul 16 2010