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 A254958 #18 Aug 28 2017 11:25:03 %S A254958 1,2,3,4,5,6,7,8,9,34,43,68,86,122,148,184,212,221,236,244,263,269, %T A254958 296,326,362,366,418,424,442,447,474,481,488,623,629,632,636,663,667, %U A254958 676,692,744,766,814,841,848,884,926,962,1111,1135,1153,1177,1224,1242,1315,1339,1351,1393,1422,1444,1513,1531,1557 %N A254958 Zeroless numbers n with digits d_1, d_2, ... d_k such that d_1^2 + ... + d_k^2 is a square. %C A254958 Any one of these terms can have an arbitrary number of 0's in between any two digits. Thus, the numbers with 0's have been omitted as trivial. %H A254958 Jonathan Schwartz, <a href="/A254958/b254958.txt">Table of n, a(n) for n = 1..1000</a> %t A254958 Select[Range[1557], (d = IntegerDigits[#]; Min[d] > 0 && IntegerQ@ Sqrt@ Total[d^2]) &] (* _Giovanni Resta_, Aug 14 2017 *) %o A254958 (PARI) for(n=1,2000,d=digits(n);if(vecsort(d,,8)[1],s=0;for(i=1,#d,s+=d[i]^2);if(issquare(s),print1(n,", ")))) %Y A254958 Cf. A000290, A003132, A052382. %K A254958 nonn,base %O A254958 1,2 %A A254958 _Derek Orr_, Feb 11 2015