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A152531 a(n) = (p(n)*p(n+2) - p(n+1))/2, where p(n) is the n-th odd prime.

%I A152531 #12 Jul 28 2015 04:16:49
%S A152531 8,24,40,87,115,186,264,342,521,617,775,942,1116,1360,1587,1946,2132,
%T A152531 2410,2768,2990,3474,3981,4446,4945,5352,5560,5991,6865,7338,8634,
%U A152531 9036,10137,10420,11621,12228,13028,14016,14860,15567,17004
%N A152531 a(n) = (p(n)*p(n+2) - p(n+1))/2, where p(n) is the n-th odd prime.
%C A152531 This is A111071 without its first term. - _R. J. Mathar_, Jul 27 2015
%F A152531 a(n) = A152530(n+1)/2.
%p A152531 A152531 := proc(n)
%p A152531     j := n+1 ;
%p A152531     ithprime(j)*ithprime(j+2)-ithprime(j+1) ;
%p A152531     %/2 ;
%p A152531 end proc: # _R. J. Mathar_, Jul 28 2015
%t A152531 (First[#]*Last[#]-#[[2]])/2&/@Partition[Prime[Range[2,50]],3,1] (* _Harvey P. Dale_, Oct 09 2014 *)
%Y A152531 Cf. A065091, A111071, A152527, A152528, A152529, A152530, A152532.
%K A152531 easy,nonn
%O A152531 1,1
%A A152531 _Omar E. Pol_, Dec 06 2008