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Numbers such that in decimal representation all permutations of digits are nonsquares.
4

%I #13 Dec 04 2022 13:39:42

%S 2,3,5,6,7,8,11,12,13,14,15,17,19,20,21,22,23,24,26,27,28,29,30,31,32,

%T 33,34,35,37,38,39,41,42,43,44,45,47,48,50,51,53,54,55,56,57,58,59,60,

%U 62,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,82,83,84,85,86,87

%N Numbers such that in decimal representation all permutations of digits are nonsquares.

%C A062892(a(n)) = 0.

%H David A. Corneth, <a href="/A096600/b096600.txt">Table of n, a(n) for n = 1..10000</a>

%e 134=2*67, 143=11*13, 314=2*157, 341=11*31, 413=7*59 and 431=A000040(83), therefore 134, 143, 314, 341, 413 and 431 are terms.

%t Select[Range[100],NoneTrue[Sqrt[#]&/@(FromDigits/@Permutations[IntegerDigits[ #]]),IntegerQ]&] (* _Harvey P. Dale_, Dec 04 2022 *)

%Y Cf. A007937, A096599, A000037, A067013.

%K nonn,easy,base

%O 1,1

%A _Reinhard Zumkeller_, Jun 29 2004