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 A052490 #4 Mar 30 2012 18:51:19 %S A052490 2,3,5,6,8,9,11,12,14,15,17,18,20,21,23,24,29,30,32,33,35,39,41,42,44, %T A052490 45,50,51,53,54,56,57,59,60,66,68,69,71,72,74,77,78,80,81,83,86,87,89, %U A052490 90,92,93,96,98,99,101,102,104,105,108,110,111,113,114,117,119,120,122 %N A052490 Numbers n with only one nonzero solution to "numbers that are n times sum of their digits". %e A052490 a(2)=3 since there is only one positive number which is three times the sum of its digits, namely 27=3*9 %Y A052490 Cf. A003634, A052489, A003635. %K A052490 base,nonn %O A052490 1,1 %A A052490 _Henry Bottomley_, Mar 16 2000