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%I A119835
%S A119835 2,3,5,7,113,857
%N A119835 Primes p such that 2*p#-1 and 2*p#+1 are twin primes.
%e A119835 2*2-1=3 2*2+1=5, 3 and 5 twin primes so a(1)=2
%e A119835 2*2*3-1=11 2*2*3+1=13, 11 and 13 twin primes so a(2)=3
%e A119835 2*2*3*5-1=59 2*2*3*5+1=61, 59 and 61 twin primes so a(3)=5
%p A119835 isA001359 := proc(n) RETURN(isprime(n) and isprime(n+2)); end: primo 
               := 2 : print(primo); for n from 2 to 20000 do p := ithprime(n); primo 
               := primo*p; if isA001359(2*primo-1) then print(p); fi; od : - R. 
               J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 09 2006
%Y A119835 Cf. A119833 A119834.
%Y A119835 Sequence in context: A006341 A086107 A046713 this_sequence A076609 A117059 
               A117058
%Y A119835 Adjacent sequences: A119832 A119833 A119834 this_sequence A119836 A119837 
               A119838
%K A119835 more,nonn
%O A119835 1,1
%A A119835 Pierre CAMI (pierrecami(AT)tele2.fr), May 25 2006

    
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Last modified November 27 22:38 EST 2009. Contains 167602 sequences.


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