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 A103390 #11 Jan 25 2020 11:36:34
%S A103390 0,1,2,3,16,5,36,7,64,81,100,11,144,13,196,225,256,17,324,19,400,441,
%T A103390 484,23,576,625,676,729,784,29,900,31,1024,1089,1156,1225,1296,37,
%U A103390 1444,1521,1600,41,1764,43,1936,2025,2116,47,2304,2401,2500,2601,2704,53
%N A103390 Natural numbers but with nonprimes squared.
%H A103390 Daniel Starodubtsev, <a href="/A103390/b103390.txt">Table of n, a(n) for n = 1..10000</a>
%H A103390 Peter Alfeld, <a href="http://www.math.utah.edu/~alfeld/math/primelist.html">The 1,000 smallest prime numbers </a>.
%e A103390 4 is not a prime, so it is squared.
%t A103390 Table[ If[ PrimeQ[n], n, n^2], {n, 0, 54}] (* _Robert G. Wilson v_, Mar 24 2005 *)
%Y A103390 Cf. A103164.
%K A103390 easy,nonn
%O A103390 1,3
%A A103390 _Parthasarathy Nambi_, Mar 20 2005
%E A103390 More terms from _Robert G. Wilson v_, Mar 24 2005