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Lesser of twin pairs in A086006.
2

%I #8 Apr 06 2023 08:30:32

%S 107,71549,97379,103067,136709,342449,403829,686969,695879,758267,

%T 795797,805499,887399,941489,945881,1023227,1025747,1081709,1081979,

%U 1169027,1179989,1261259,1456919,1554101,2110877,2148659,2167469,2433059,2494439,2554397,2623571,2803121

%N Lesser of twin pairs in A086006.

%C Primes p such that both p and p+2 are terms in A086006.

%H Amiram Eldar, <a href="/A158476/b158476.txt">Table of n, a(n) for n = 1..10000</a>

%H Zak Seidov, <a href="http://zak08.livejournal.com/7613.html">First 100 terms</a>.

%t Select[Prime[Range[10^6]], PrimeQ[# + 2] && PrimeOmega[2*# - 1] == PrimeOmega[2*# + 1] == 2 && PrimeOmega[2*# + 3] == PrimeOmega[2*# + 5] == 2 &] (* _Amiram Eldar_, Apr 06 2023 *)

%o (PARI) is(p) = (bigomega(2*p+1) == 2) && (bigomega(2*p-1) == 2);

%o lista(max) = {my(q1 = 0, q2, prev = 0); forprime(p = 2, max, q2 = is(p); if(p == prev + 2 && q1 && q2, print1(prev, ", ")); prev = p; q1 = q2);} \\ _Amiram Eldar_, Apr 06 2023

%Y Cf. A086005, A086006.

%K nonn

%O 1,1

%A _Zak Seidov_, Mar 20 2009

%E More terms from _Amiram Eldar_, Apr 06 2023