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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.
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%I #32 Feb 19 2015 14:45:19

%S 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 73,78,82,86,108,109,113,129,132,147,151,152,154,155,159,164,165,166,

%U 168,172,173,181,193,206,211,229,231,241,260,262,271,272,277,286

%N 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 a(8)=10 because 108+41=149 where 149 is a twin primes and A014574(10)=108, A001097(10)=41.

%p isA001097 := proc(n)

%p if isprime(n) then

%p if isprime(n+2) or isprime(n-2) then

%p true;

%p else

%p false;

%p end if;

%p else

%p false;

%p end if;

%p end proc:

%p # see A001097 and A014574 for the other pieces of the Maple program

%p for n from 1 to 300 do

%p if isA001097(A001097(n)+A014574(n)) then

%p printf("%d,",n);

%p end if;

%p end do: # _R. J. Mathar_, Feb 19 2015

%Y Cf. A001097, A014574.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Dec 18 2011

%E Corrected by _R. J. Mathar_, Feb 19 2015