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 A171672 #18 Mar 26 2025 17:49:22
%S A171672 1,3,8,11,20,76,83,86,94,97,104,110,133,137,166,173,176,184,187,194,
%T A171672 223,256,263,264,266,274,275,277,284,332,353,356,364,367,396,403,407,
%U A171672 436,443,454,457,464,504,533,535,546,587,623,624,625,634,637,644,654,673
%N A171672 Numbers m with property that m^2 is not of form (k + sum of digits of k).
%H A171672 Amiram Eldar, <a href="/A171672/b171672.txt">Table of n, a(n) for n = 1..10000</a>
%H A171672 Zak Seidov, <a href="http://zak08.livejournal.com/17915.html">Self squares</a>.
%H A171672 Zak Seidov, <a href="http://zak08.livejournal.com/18144.html">A171672: n^2 is safe number</a>.
%F A171672 a(n) = sqrt(A171671(n)).
%t A171672 nn=5*10^5; list=Table[n + Total[IntegerDigits[n]],{n,nn}]; Select[Sqrt[Complement[Range[nn],list]], IntegerQ[#] &] (* _Jayanta Basu_, May 06 2013 *)
%Y A171672 Cf. A003052 (self or Colombian numbers), A171671 (m^2 are self numbers), A062028 (a(n) = n + sum of the digits of n), A171673 (n and n^2 are self numbers).
%K A171672 base,nonn
%O A171672 1,2
%A A171672 _Zak Seidov_, Dec 15 2009
%E A171672 Changed the word "safe" in this entry to "self". - _N. J. A. Sloane_, Feb 26 2017