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%I #8 Jan 05 2019 23:26:47
%S 12011,12041,13049,18041,21011,22013,28019,29021,29033,31019,33023,
%T 37013,37049,38039,42023,43013,48029,1110269,1120349,1120481,1130273,
%U 1130429,1140143,1140311,1140341,1140383,1140413,1140449,1160129,1160213,1160429,1170173,1170329,1170443
%N Cyclops primes p such that 2p+1 is also a Cyclops prime.
%C Primes p such that both p and 2p+1 are Cyclops primes A134809.
%C By definition all terms are also Sophie Germain primes A005384.
%e a(1) = 12011 is in the sequence because 12011 is a Cyclops prime A134809 and 2*12011+1 = 24023 is also a Cyclops prime.
%p isA134808 := proc(n) local dgs,ndgs; dgs := convert(n,base,10) ; mdg := (nops(dgs)+1)/2 ; if type(nops(dgs),'even') then false; elif n = 0 then true; else if op(mdg,dgs) <> 0 then false; else if mul(op(k,dgs),k=1..mdg-1) =0 or mul(op(k,dgs),k=mdg+1..nops(dgs)) = 0 then false; else true; end if; end if; end if; end proc:
%p isA134809 := proc(n) isprime(n) and isA134808(n) ; end proc:
%p isA183059 := proc(n) isA134809(n) and isA134809(2*n+1) ; end proc:
%p for n from 0 to 1200000 do if isA183059(n) then printf("%d,",n); end if; end do: # _R. J. Mathar_, Jan 05 2011
%Y Cf. A005384, A134808, A134809, A183058.
%K nonn,base,less
%O 1,1
%A _Omar E. Pol_, Dec 25 2010
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