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 A104262 #6 Mar 13 2019 18:52:16
%S A104262 149,496481,361400441,202521162209,562557765929,624164006561,
%T A104262 98011000010201,118811210012321,198812016420449,272252755627889,
%U A104262 342253459634969,778417840078961,789617952480089,906019120491809
%N A104262 Primes which are the concatenation of three consecutive square numbers.
%H A104262 Harvey P. Dale, <a href="/A104262/b104262.txt">Table of n, a(n) for n = 1..1000</a>
%e A104262 The first term is 149 which is a prime and is the concatenation of 1,4 and 9 which are three consecutive square numbers.
%t A104262 c3sn[{a_,b_,c_}]:=FromDigits[Flatten[IntegerDigits/@{a,b,c}]]; Select[ c3sn/@ Partition[Range[400]^2,3,1],PrimeQ] (* _Harvey P. Dale_, Mar 13 2019 *)
%K A104262 base,nonn
%O A104262 1,1
%A A104262 _Shyam Sunder Gupta_, Apr 17 2005