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 A165550 #8 Aug 16 2017 17:10:37 %S A165550 0,1,2,3,10,20,30,33,100,200,300,330,333,1000,1143,1431,2000,2242, %T A165550 3000,3233,3300,3330,3331,3333,3411,3433,4131,10000,11234,11243,11344, %U A165550 11403,11430,11432,11433,12235,12523,13134,13142,13144,13241,13431,13522 %N A165550 Sum of digits of square is sum of square of digits. %H A165550 Rémy Sigrist, <a href="/A165550/b165550.txt">Table of n, a(n) for n = 1..10000</a> %e A165550 Consider n=33: n^2 is 1089, sum of square of digits is 3^2+3^2=18, and sum of digits of square is 1+0+8+9=18, thus 33 appears in the sequence. %o A165550 (PARI) digsum(n) = my(s=0); while(n,s=s+n%10;n=n\10); s; %o A165550 sqadigsum(n) = my(s=0); while(n,s=s+(n%10)^2;n=n\10); s; %o A165550 for(n=0,100000, if(sqadigsum(n)==digsum(n^2), print1(n, ",") ) ) %K A165550 base,easy,nonn %O A165550 1,3 %A A165550 _Rémy Sigrist_, Sep 21 2009 %E A165550 Offset fixed by _Rémy Sigrist_, Feb 03 2017