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A193687 Numbers n such that the sum of n-th average of a twin prime pair and the n-th twin prime is also a twin prime.

%I A193687 #32 Feb 19 2015 14:45:19
%S A193687 1,2,3,4,5,6,8,10,11,13,15,22,24,32,35,36,43,44,53,55,59,67,68,70,71,
%T A193687 73,78,82,86,108,109,113,129,132,147,151,152,154,155,159,164,165,166,
%U A193687 168,172,173,181,193,206,211,229,231,241,260,262,271,272,277,286
%N A193687 Numbers n such that the sum of n-th average of a twin prime pair and the n-th twin prime is also a twin prime.
%e A193687 a(8)=10 because 108+41=149 where 149 is a twin primes and A014574(10)=108, A001097(10)=41.
%p A193687 isA001097 := proc(n)
%p A193687     if isprime(n) then
%p A193687         if isprime(n+2) or isprime(n-2) then
%p A193687             true;
%p A193687         else
%p A193687             false;
%p A193687         end if;
%p A193687     else
%p A193687         false;
%p A193687     end if;
%p A193687 end proc:
%p A193687 # see A001097 and A014574 for the other pieces of the Maple program
%p A193687 for n from 1 to 300 do
%p A193687     if isA001097(A001097(n)+A014574(n)) then
%p A193687         printf("%d,",n);
%p A193687     end if;
%p A193687 end do: # _R. J. Mathar_, Feb 19 2015
%Y A193687 Cf. A001097, A014574.
%K A193687 nonn
%O A193687 1,2
%A A193687 _Juri-Stepan Gerasimov_, Dec 18 2011
%E A193687 Corrected by _R. J. Mathar_, Feb 19 2015