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A280648
Numbers k such that k^3 has an odd number of digits and the middle digit is 8.
3
2, 24, 35, 38, 120, 127, 131, 138, 145, 172, 174, 182, 183, 208, 212, 215, 471, 481, 482, 485, 495, 505, 516, 517, 544, 551, 567, 594, 601, 610, 617, 621, 644, 646, 674, 677, 689, 736, 739, 749, 756, 768, 773, 774, 775, 776, 786, 799, 803, 812, 821, 830, 835
OFFSET
1,1
COMMENTS
The sequence of cubes starts: 8, 13824, 42875, 54872, 1728000, 2048383, 2248091, 2628072, ...
LINKS
Jeremy Gardiner, Middle digit in cube numbers, Seqfan Mailing list, Dec 12 2016.
EXAMPLE
2^3 = (8), 172^3 = 508(8)448, 610^3 = 2269(8)1000.
MATHEMATICA
Select[Range[835], OddQ[len=Length[IntegerDigits[#^3]]]&&Part[IntegerDigits[#^3], (len+1)/2]==8 &] (* Stefano Spezia, Oct 03 2023 *)
CROSSREFS
See A279420-A279429 for a k^2 version.
See A279430-A279431 for a k^2 version in base 2.
Sequence in context: A212759 A112660 A330526 * A339403 A119066 A019996
KEYWORD
nonn,base,easy
AUTHOR
Lars Blomberg, Jan 07 2017
STATUS
approved