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%I #11 Jun 19 2019 21:04:49
%S 0,0,0,0,0,0,0,16,16,36,36,36,36,64,64,96,96,96,96,136,136,136,136,
%T 136,136,188,188,188,188,188,188,188,188,256,256,256,256,256,256,336,
%U 336,336,336,424,424,424,424,424
%N The sum of the positive integers not exceeding 2n that are representable as the sum of two successive sexy primes.
%C 4 divides a(n) for n > 0.
%F a(n) = 2*Sum_{i=1..n} i * (pi(i-3) - pi(i-4)) * (pi(i+3) - pi(i+2)), where pi is the prime counting function (A000720).
%F a(n) = Sum_{i=1..2*n} c(i), where c is the characteristic function of A104010. - _R. J. Mathar_, May 28 2013
%p with(numtheory); A226068:=n->sum( 2*i*(pi(i-3) - pi(i-4)) * (pi(i+3) - pi(i+2)) , i = 1..n);
%p seq(A226068(k), k = 1..70);
%Y Cf. A000720, A104010, A098428.
%K nonn
%O 1,8
%A _Wesley Ivan Hurt_, May 24 2013
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