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%I #13 Jan 24 2022 10:01:17
%S 2,3,8,15,12,21,32,36,40,55,72,65,56,90,64,119,144,57,120,168,132,161,
%T 240,200,156,270,168,203,360,155,320,396,136,350,432,333,380,546,320,
%U 369,672,387,352,810,368,423,672,294,600,816,520,583,864,660,784
%N Sum of all primes p such that 2n - p is also a prime.
%C Sum of n-th row in triangle A171637.
%H Reinhard Zumkeller, <a href="/A238778/b238778.txt">Table of n, a(n) for n = 2..10000</a>
%F a(n) = A008472(A238711(n)).
%F a(n) mod 2 = A010051(n).
%F a(n) = n*A035026(n). - _Robert G. Wilson v_, Apr 28 2018
%o (Haskell)
%o a238778 n = sum $ filter ((== 1) . a010051') $
%o map (2 * n -) $ takeWhile (<= 2 * n) a000040_list
%o (PARI) a(n) = my(s=0); forprime(p=2, 2*n, if(isprime(2*n-p), s+=p)); s; \\ _Michel Marcus_, Jan 24 2022
%Y Cf. A008472, A238711.
%Y Cf. A010051, A035026, A171637
%K nonn
%O 2,1
%A _Reinhard Zumkeller_, Mar 06 2014