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%I #25 Oct 12 2018 19:58:23
%S 5,15,27,33,57,93,105,165,177,189,231,237,245,267,275,285,345,375,393,
%T 425,453,555,567,573,597,609,637,651,687,723,833,933,1005,1025,1095,
%U 1167,1209,1221,1227,1293,1311,1431,1445,1479,1491,1527,1551,1563,1573
%N Numbers k such that both k - tau(k) and k + tau(k) are prime where tau(k) = A000005(k).
%H Marius A. Burtea, <a href="/A067533/b067533.txt">Table of n, a(n) for n = 1..1128 </a>
%e 57 is a term as tau(57) = 4 and 57-4 = 53 and 57+4 = 61 are both primes.
%o (PARI) isok(n) = my(nd = numdiv(n)); isprime(n-nd) && isprime(n+nd); \\ _Michel Marcus_, Oct 12 2018
%Y Intersection of A067531 and A067532.
%K easy,nonn
%O 1,1
%A _Amarnath Murthy_, Feb 17 2002
%E More terms from _Sascha Kurz_, Mar 19 2002
%E Offset corrected by _Alois P. Heinz_, Oct 10 2018
%E Name changed by _David A. Corneth_, Oct 12 2018