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A087901 Twin primes associated with A087900.

%I A087901 #16 Jun 22 2025 00:16:31
%S A087901 5,7,29,31,179,181,1619,1621,21059,21061,463319,463321,11119679,
%T A087901 11119681,567103679,567103681,52173538559,52173538561,6260824627199,
%U A087901 6260824627201,1101905134387199,1101905134387201,284291524671897599,284291524671897601,77895877760099942399,77895877760099942401
%N A087901 Twin primes associated with A087900.
%H A087901 Robert Israel, <a href="/A087901/b087901.txt">Table of n, a(n) for n = 1..418</a>
%F A087901 From _Robert Israel_, Jun 11 2025: (Start)
%F A087901 a(2*n-1) = (Product_{i=1..n+1} A087900(i)) - 1.
%F A087901 a(2*n) = (Product_{i=1..n+1} A087900(i)) + 1. (End)
%p A087901 R:= NULL; s:= 2: count:= 0:
%p A087901 for r from 3 while count < 30 do
%p A087901     if isprime(s*r+1) and isprime(s*r-1) then
%p A087901       count:= count+2; s:= s*r; R:= R,s-1,s+1;
%p A087901     fi;
%p A087901 od:
%p A087901 R; # _Robert Israel_, Jun 11 2025
%Y A087901 Cf. A087900.
%K A087901 nonn,tabf
%O A087901 1,1
%A A087901 _Lekraj Beedassy_, Oct 14 2003