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 A051671 #7 May 18 2013 16:49:27 %S A051671 4,9,284,61209,14204828164,4440027571600000000001, %T A051671 7667716927194638935286982918857620344809476 %N A051671 Smallest positive number whose digits concatenated with all previous terms forms a perfect square. %D A051671 A. Murthy, Smar. Notions J. Vol. 11 N. 1-2-3 Spring 2000. %e A051671 284 belongs to the sequence because 49284=222^2. %Y A051671 Cf. A048559, A048560, A051670. %K A051671 nice,nonn,easy,base %O A051671 0,1 %A A051671 _Felice Russo_ %E A051671 More terms from _Patrick De Geest_, Dec 15 1999