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%I #9 Oct 03 2023 20:04:19
%S 22,25,27,36,37,124,129,134,147,156,160,169,469,497,503,527,532,540,
%T 547,548,549,565,571,587,602,609,652,670,672,678,688,698,713,716,722,
%U 735,741,746,751,754,755,789,794,797,798,805,813,820,828,849,866,883,887
%N Numbers k such that k^3 has an odd number of digits and the middle digit is 6.
%C The sequence of cubes starts: 10648, 15625, 19683, 46656, 50653, 1906624, 2146689, 2406104, ...
%H Lars Blomberg, <a href="/A280646/b280646.txt">Table of n, a(n) for n = 1..10000</a>
%H Jeremy Gardiner, <a href="http://list.seqfan.eu/oldermail/seqfan/2016-December/017135.html">Middle digit in cube numbers</a>, Seqfan Mailing list, Dec 12 2016.
%e 22^3 = 10(6)48, 156^3 = 379(6)416, 678^3 = 3116(6)5752.
%t Select[Range[887], OddQ[len=Length[IntegerDigits[#^3]]]&&Part[IntegerDigits[#^3], (len+1)/2]==6 &] (* _Stefano Spezia_, Oct 03 2023 *)
%Y Cf. A280640-A280645, A280647-A280649, A181354.
%Y See A279420-A279429 for a k^2 version.
%Y See A279430-A279431 for a k^2 version in base 2.
%K nonn,base,easy
%O 1,1
%A _Lars Blomberg_, Jan 07 2017
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