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%I #12 Sep 14 2017 05:54:45
%S 19,31,41,71,79,89,101,103,113,127,139,197,199,223,271,281,307,349,
%T 353,367,379,401,439,449,461,463,491,499,521,571,607,617,619,641,643,
%U 701,727,739,761,769,811,821,859,881,911,919,929,941,953,967,991,1039,1061
%N Primes p such that sums of divisors of the two adjacent integers are each > 2*p.
%H G. C. Greubel, <a href="/A164320/b164320.txt">Table of n, a(n) for n = 1..5000</a>
%F Intersection of A164318 and A164319.
%e For p=19, the sum of the divisors of 18 is A000203(18)=39 > 2*19, and the sum of the divisors
%e of 20 is A000203(20)= 42 > 2*19, so p=19 is in the sequence.
%t f[n_]:=Plus@@Divisors[n]; lst={};Do[p=Prime[n];If[f[p-1]>2*p&&f[p+1]> 2*p,AppendTo[lst,p]],{n,6!}];lst
%t Select[Prime[Range[200]],DivisorSigma[1,#-1]>2#&&DivisorSigma[ 1,#+1]>2#&] (* _Harvey P. Dale_, Nov 10 2011 *)
%Y Cf. A164318, A164319.
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Aug 12 2009
%E References to unrelated sequences removed by _R. J. Mathar_, Aug 21 2009
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