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A107627 Numbers n such that every digit of n and sqrt(n) contains a loop (only digits 0,4,6,8,9 in n and sqrt(n)). 2

%I #8 Oct 01 2023 16:21:26

%S 64,4096,6400,9604,409600,440896,640000,806404,960400,996004,40960000,

%T 44089600,44408896,64000000,80640400,80964004,96040000,99600400,

%U 99960004

%N Numbers n such that every digit of n and sqrt(n) contains a loop (only digits 0,4,6,8,9 in n and sqrt(n)).

%C Corresponding square roots in A107626. Cf. A001744 Every digit contains a loop.

%H Harvey P. Dale, <a href="/A107627/b107627.txt">Table of n, a(n) for n = 1..100</a>

%t Do[id=Union[IntegerDigits[n^2], IntegerDigits[n]];If[Count[id, 1]+Count[id, 2]+Count[id, 3]+Count[id, 5]+Count[id, 7]==0, Print[n^2]], {n, 10000}]

%t With[{c={0,4,6,8,9}},#^2&/@Select[FromDigits/@Tuples[c,4],SubsetQ[c,IntegerDigits[ #^2]]&]] (* _Harvey P. Dale_, Oct 01 2023 *)

%Y Cf. A001744, A107624, A107625, A107626.

%K nonn,base,dumb

%O 1,1

%A _Zak Seidov_, May 18 2005

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Last modified March 29 09:59 EDT 2024. Contains 371268 sequences. (Running on oeis4.)