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%I #7 Oct 03 2023 18:44:52
%S 3,14,114,118,130,134,148,158,161,170,173,176,187,212,219,228,230,270,
%T 272,281,288,313,1034,1039,1044,1058,1063,1072,1077,1086,1095,1109,
%U 1118,1131,1140,1153,1166,1183,1204,1208,1292,1296,1315,1319,1334,1345,1349
%N Numbers k such that k^2 has an odd number of digits and the middle digit is 9.
%H Lars Blomberg, <a href="/A279429/b279429.txt">Table of n, a(n) for n = 1..10000</a>
%e 3^2 = (9), 170^2 = 28(9)00, 1086^2 = 117(9)396.
%t Select[Range[1349], OddQ[len=Length[IntegerDigits[#^2]]]&&Part[IntegerDigits[#^2], (len+1)/2]==9 &] (* _Stefano Spezia_, Oct 03 2023 *)
%Y Cf. A279420-A279428.
%K nonn,base,easy
%O 1,1
%A _Lars Blomberg_, Dec 22 2016
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