%I #6 Dec 29 2019 17:59:37
%S 10,13,18,19,22,27,28,31,37,40,45,46,54,55,58,63,67,72,73,76,82,85,90,
%T 91,94,99,103,108,109,112,117,118,126,127,130,135,136,139,145,148,153,
%U 154,157,162,163,166,171,172,175,180,181,184,189,190,193,198,199,202
%N Integers congruent to 0, 1 or 4 (mod 9) which are not squares.
%D Mark A. Herkommer, Number Theory, A Programmer's Guide, McGraw-Hill, New York, 1999, page 315.
%t Select[ Range[206], (Mod[ #, 9] == 0 || Mod[ #, 9] == 1 || Mod[ #, 9] == 4) && !IntegerQ[ Sqrt[ # ]] & ]
%t Select[Flatten[#+{0,1,4}&/@(9*Range[0,30])],!IntegerQ[Sqrt[#]]&] (* _Harvey P. Dale_, Dec 29 2019 *)
%Y Cf. A028837.
%K easy,nonn
%O 1,1
%A _Robert G. Wilson v_, Mar 26 2003
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