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 A152867 #5 Mar 30 2012 17:27:56
%S A152867 13,89,809,4561,6689,7603,11321,16493,18229,22153,24107,28409,28687,
%T A152867 29153,32749,33013,54493,55663,63337,63419,67169,86011,90289,108881,
%U A152867 113647,116929,132589,133187,136033,136403,137791,145543,147353,150583
%N A152867 Beginnings of maximal chains of primes with four members (three links).
%C A152867 For definitions see A152658, of which this is a subsequence.
%H A152867 Klaus Brockhaus, <a href="/A152867/b152867.txt">Table of n, a(n) for n=1..1000</a>
%e A152867 First maximal chain of primes with four members (three links) is 13, 17, 19, 23; the linking primes are 197, 271, 359.
%o A152867 (PARI) {n=1; while(n<13900, c=0; a=prime(n); while(isprime(n*prime(n)+(n+1)*prime(n+1)), c++; n++); if(c==3, print1(a, ",")); n++)}
%Y A152867 Cf. A152658 (beginnings of maximal chains of primes), A152735 (count of links in n-th maximal chain of primes), A152962 (beginning of the first maximal chain of primes with n links), A152865, A152866, A152868, A152869, A152963, A152964.
%K A152867 nonn
%O A152867 1,1
%A A152867 _Klaus Brockhaus_, Dec 17 2008