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%I #14 Apr 16 2024 02:40:12
%S 3,8,30,68,277,600,1444,2123,3128,3230,3672,3783,4441,5016,5052,5144,
%T 5304,5665,6353,6468,6513,6588,6772,6983,7044,7087,8392,8418,8632,
%U 8866,9217,9264,9292,9540,9917,9949,10495,11429,11532,13474,14063,15431
%N Numbers k such that prime(k+2)-(k+2)*tau(k+2) = prime(k-2)-(k-2)*tau(k-2) where tau(k) = A000005(k) is the number of divisors of k.
%H Amiram Eldar, <a href="/A067354/b067354.txt">Table of n, a(n) for n = 1..10000</a>
%t Select[Range[3,16000],Prime[#-2]-(#-2)DivisorSigma[0,#-2]==Prime[#+2]-(#+2)DivisorSigma[0,#+2]&] (* _Harvey P. Dale_, Dec 20 2015 *)
%o (PARI) f(n) = prime(n) - n * numdiv(n);
%o is(n) = n > 2 && f(n-2) == f(n+2); \\ _Amiram Eldar_, Apr 16 2024
%Y Cf. A000005, A067292, A067293, A067335, A067355, A067356.
%K easy,nonn,changed
%O 1,1
%A _Benoit Cloitre_, Feb 24 2002
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