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 A081643 #6 Jul 29 2019 20:13:09
%S A081643 17,20,32,33,41,48,52,57,65,68,73,80,84,89,96,97,105,112,113,116,128,
%T A081643 129,132,137,145,148,153,160,161,164,176,177,180,185,192,193,201,208,
%U A081643 209,212,217,224,228,233,240,241,244,249,257,260,265,272,273,276,281
%N A081643 Integers congruent to 0, 1, 4 or 9 (mod 16) which are not squares.
%D A081643 Mark A. Herkommer, Number Theory, A Programmer's Guide, McGraw-Hill, New York, 1999, page 315.
%H A081643 Harvey P. Dale, <a href="/A081643/b081643.txt">Table of n, a(n) for n = 1..1000</a>
%t A081643 Select[ Range[287], (Mod[ #, 16] == 0 || Mod[ #, 16] == 1 || Mod[ #, 16] == 4 || Mod[ #, 16] == 9) && !IntegerQ[ Sqrt[ # ]] & ]
%t A081643 Select[Range[300],MemberQ[{0,1,4,9},Mod[#,16]]&&!IntegerQ[Sqrt[#]]&] (* _Harvey P. Dale_, Jul 29 2019 *)
%K A081643 easy,nonn
%O A081643 1,1
%A A081643 _Robert G. Wilson v_, Mar 26 2003