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%I #8 Feb 19 2019 18:22:22
%S 24,26,42,52,61,69,74,76,82,84,85,88,124,131,132,144,154,165,166,174,
%T 181,189,194,218,224,226,234,239,240,260,265,266,269,271,274,275,276,
%U 319,326,356,371,376,384,415,416,418,419,420,421,448,455,466,474,476,520,521,524,525,526,552
%N Numbers n such that the largest digit of n^2 is 7.
%H Robert Israel, <a href="/A295007/b295007.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = sqrt(A295017(n)), where sqrt = A000196 or A000194 or A003059.
%e 24 is in this sequence because 24^2 = 576 has 7 as largest digit.
%p filter:= proc(n) max(convert(n^2,base,10))=7 end proc:
%p select(filter, [$1..1000]); # _Robert Israel_, Feb 19 2019
%o (PARI) select( is_A295007(n)=n&&vecmax(digits(n^2))==7 , [0..999]) \\ The "n&&" avoids an error message for n=0.
%Y Cf. A295017 (the corresponding squares), A277959 .. A277961 (same for digit 2 .. 4), A295005 .. A295009 (same for digit 5 .. 9).
%Y Cf. A000290 (the squares).
%K nonn,base
%O 1,1
%A _M. F. Hasler_, Nov 12 2017
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