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 A057602 #13 Mar 02 2015 18:06:27
%S A057602 2,4,6,9,15,25,35,49,77,121,143,169,221,289,323,361,437,529,667,841,
%T A057602 899,961,1147,1369,1517,1681,1763,1849,2021,2209,2491,2809,3127,3481,
%U A057602 3599,3721,4087,4489,4757,5041,5183,5329,5767,6241,6557,6889,7387,7921
%N A057602 a(1)=2, a(n+1) is the smallest integer > a(n) such that the smallest prime factor of a(n+1) is the largest prime factor of a(n).
%H A057602 Harvey P. Dale, <a href="/A057602/b057602.txt">Table of n, a(n) for n = 1..1000</a>
%F A057602 Even numbered terms are squares of successive primes. Odd numbered terms are the product of two successive primes and are the square root of the product of the previous term and the next term - _Jud McCranie_, Oct 07 2000
%t A057602 Module[{nn=30,pr,ev,od},pr=Prime[Range[nn]];ev=pr^2;od=Times @@@ Partition[ pr,2,1];Join[{2},Riffle[ev,od]]] (* _Harvey P. Dale_, Mar 02 2015 *)
%Y A057602 Cf. A000040.
%Y A057602 A033476.
%K A057602 nonn
%O A057602 1,1
%A A057602 _G. L. Honaker, Jr._, Oct 07 2000
%E A057602 Additional terms from _Jud McCranie_, Oct 07 2000