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%I #10 Oct 03 2023 16:08:01
%S 2,24,35,38,120,127,131,138,145,172,174,182,183,208,212,215,471,481,
%T 482,485,495,505,516,517,544,551,567,594,601,610,617,621,644,646,674,
%U 677,689,736,739,749,756,768,773,774,775,776,786,799,803,812,821,830,835
%N Numbers k such that k^3 has an odd number of digits and the middle digit is 8.
%C The sequence of cubes starts: 8, 13824, 42875, 54872, 1728000, 2048383, 2248091, 2628072, ...
%H Lars Blomberg, <a href="/A280648/b280648.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 2^3 = (8), 172^3 = 508(8)448, 610^3 = 2269(8)1000.
%t Select[Range[835], OddQ[len=Length[IntegerDigits[#^3]]]&&Part[IntegerDigits[#^3], (len+1)/2]==8 &] (* _Stefano Spezia_, Oct 03 2023 *)
%Y Cf. A280640-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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