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%I #4 Dec 05 2013 19:55:37
%S 1,2,9,19,20,41,42,43,44,89,90,181,182,547,548,1097,1098,7687,7688,
%T 15377,15378,30757,30758,276823,276824,553649,553650,2768251,2768252,
%U 8304757,8304758,99657097,99657098,199314197,199314198,3189027169
%N a(1) = 1; a(2n) is the smallest prime == 1 mod (a(2n-1)) and a(2n+1) is the smallest composite number == 1 (mod a(2n)).
%Y Cf. A075341.
%K nonn
%O 1,2
%A _Amarnath Murthy_, Sep 18 2002
%E More terms from _David Wasserman_, Jan 16 2005