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 A080470 #8 Dec 05 2013 19:56:00 %S A080470 10,12,30,4,15,6,27,8,9,10,110,12,123,14,15,16,117,18,119,20,21,22, %T A080470 123,24,25,26,27,28,129,30,231,32,33,34,35,36,237,38,39,40,141,42,143, %U A080470 44,45,46,147,48,49,50,51,52,153,54,55,56,57,58,159,60,161,62,63,64,65,66,267 %N A080470 a(n) = smallest composite number that is obtained by placing digits anywhere in n; a(n) = n if n is composite. %Y A080470 Cf. A062584, A068164, A068165. %K A080470 base,nonn %O A080470 1,1 %A A080470 _Amarnath Murthy_, Mar 07 2003 %E A080470 Corrected and extended by _Ray Chandler_, Oct 11 2003