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Numbers k such that the k-th sum of two successive primes is a twin prime average.
2

%I #14 Jan 23 2020 09:22:14

%S 3,4,6,8,10,19,25,30,50,62,63,79,80,85,112,117,120,127,131,140,145,

%T 149,159,175,177,217,235,261,264,289,303,309,319,320,333,335,373,382,

%U 394,401,402,410,436,442,446,456,462,469,471,476,477,487,513,525,527,537

%N Numbers k such that the k-th sum of two successive primes is a twin prime average.

%H Amiram Eldar, <a href="/A176986/b176986.txt">Table of n, a(n) for n = 1..10000</a>

%F {k: A001043(k) in A014574}.

%p A001043 := proc(n) ithprime(n)+ithprime(n+1) ; end proc:

%p A014574 := proc(n) (A001359(n)+A006512(n))/2 ; end proc:

%p isA014574 := proc(n) local k ; for k from 1 do av := A014574(k) ; if av> n then return false; elif av=n then return true; end if; end do; end proc:

%p for n from 1 to 800 do if isA014574(A001043(n) ) then printf("%d,",n) ; end if; end do: # _R. J. Mathar_, Apr 30 2010

%Y Cf. A001043, A001359, A014574.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Apr 30 2010

%E Corrected (95 replaced by 85, 394 inserted) and extended by _R. J. Mathar_, Apr 30 2010