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Twin A045954's (middle terms) that are primes.
1

%I #18 Mar 20 2024 03:11:38

%S 3,5,11,19,43,53,101,131,139,149,197,229,373,389,419,523,547,587,643,

%T 709,739,883,997,1091,1093,1187,1483,1621,1931,1973,2099,2243,2347,

%U 2357,2411,2549,2677,2731,2741,2803,2963,3011,3203,3307,3331,3461,3467,3541,3733

%N Twin A045954's (middle terms) that are primes.

%C Also, prime terms of A045957. - _Sean A. Irvine_, Mar 29 2021

%H Amiram Eldar, <a href="/A045961/b045961.txt">Table of n, a(n) for n = 1..10000</a>

%t evenLuckies[max_] := Module[{lst = Range[2, max, 2], i = 2, len}, While[i <= (len = Length@lst) && (k = lst[[i]]) <= len, lst = Drop[lst, {k, len, k}]; i++]; lst]; twinMid[max_] := Module[{s = evenLuckies[max]}, Select[s[[Position[ Differences[s], 2] // Flatten]] + 1, PrimeQ]]; twinMid[3800] (* _Amiram Eldar_, Mar 20 2024, after _Robert G. Wilson v_ at A045954 *)

%Y Intersection of A000040 and A045957.

%Y Cf. A045954.

%K nonn

%O 1,1

%A _Felice Russo_

%E More terms from _David W. Wilson_