This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A270639 #17 Jun 28 2019 16:37:02
%S A270639 13741,16705,150851,208465,249841,252601,258511,410041,486737,635401,
%T A270639 1052503,1082401,1457773,1507963,1579249,1615681,2113921,2184571,
%U A270639 3090091,3375487,3726541,4682833,4895065,5044033,5133201,6233977,6255341,6350941,6474691,6912079,7259161
%N A270639 Fermat pseudoprimes (A001567) that are the sum of three consecutive primes.
%C A270639 In other words, Fermat pseudoprimes to base 2 of the form p + q + r where p, q and r are consecutive primes.
%C A270639 If a Fermat pseudoprime is the sum of n consecutive primes, it is so obvious that the minimum value of n is 3.
%C A270639 Intersection of A001567 and A034961.
%H A270639 Amiram Eldar, <a href="/A270639/b270639.txt">Table of n, a(n) for n = 1..10000</a>
%e A270639 4567, 4583 and 4591 are consecutive primes and their sum is 13741, a Fermat pseudoprime.
%e A270639 84191, 84199 and 84211 are consecutive primes and their sum is 252601, a Fermat pseudoprime.
%o A270639 (PARI) isA001567(n) = {Mod(2, n)^n==2 && !ispseudoprime(n) && n > 1}
%o A270639 a034961(n) = my(p=prime(n), q=nextprime(p+1)); p+q+nextprime(q+1);
%o A270639 for(n=1, 200000, if(isA001567(a034961(n)), print1(a034961(n), ", ")));
%Y A270639 Cf. A001567, A034961, A270267.
%K A270639 nonn
%O A270639 1,1
%A A270639 _Altug Alkan_, Mar 20 2016