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%I #12 May 12 2019 02:18:07
%S 1,2,0,2,6,8,4,2,0,8,12,2,12,8,8,14,20,4,8,0,2,18,22,16,10,2,24,8,24,
%T 38,24,32,32,6,2,4,44,5,8,2,30,32,16,2,0,8,16,36,2,46,8,56,17,4,43,16,
%U 32,20,42,8,8,44,2,64,8,32,4,2,48,27,64,88,2,44,8,32,23,54,44,18
%N a(n) = 2^(positive nonprime(n)-1) mod (positive nonprime(n+1)).
%F a(n) = 2^(A018252(n)-1) mod A018252(n+1).
%e a(4)=2 because 2^(A018252(4)-1) = 2^7 = 128 mod A018252(4+1) = 10.
%p A175802 := proc(n) local n1,n2 ; n1 := A018252(n) ; n2 := A018252(n+1) ; (2^(n1-1)) mod n2 ; end proc: # _R. J. Mathar_, Dec 05 2010
%Y Cf. A018252.
%K nonn,less
%O 1,2
%A _Juri-Stepan Gerasimov_, Dec 04 2010
%E Corrected by _R. J. Mathar_, Dec 05 2010