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%I #29 Jul 01 2023 16:53:49
%S 1,1360,1361,1362,1363,1364,1365,1366,1367,1368,1370,1371,1372,1373,
%T 1374,1375,1376,1377,1378,1379,2490,2491,2492,2493,2494,2495,2496,
%U 2497,2498,2499,2500,2501,2502,2503,2504,2505,2506,2507,2508,2509,3590,3591,3592,3593
%N Numbers k such that the integer part of the square root of k appears in the middle of the decimal expansion of k.
%C Subsequence of A133785.
%H Michel Lagneau, <a href="/A242458/b242458.txt">Table of n, a(n) for n = 1..9445</a>
%e a(2)=1360 because floor(sqrt(1360)) = 36 occurs in the middle of 1360.
%t lst={};Do[a=IntegerDigits[n];b=Length[a];c=IntegerLength[Floor[Sqrt[n]]];If[EvenQ[b-c]&&FromDigits[Take[a,{(b-c)/2+1,(b+c)/2}]]==Floor[Sqrt[n]], AppendTo[lst,n]],{n,10^5}];lst
%Y Cf. A133785.
%K nonn,base
%O 1,2
%A _Michel Lagneau_, Jun 08 2014
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