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A125497 Evil cubes. 1
0, 27, 125, 216, 343, 729, 1000, 1331, 1728, 2744, 3375, 4913, 5832, 6859, 8000, 9261, 10648, 13824, 19683, 21952, 27000, 29791, 35937, 39304, 46656, 50653, 54872, 59319, 64000, 68921, 74088, 85184, 103823, 110592, 148877, 157464, 166375 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

125 is in the sequence because 5^3 = 125 and its representation in base 2 (1111101) has an even number of 1's.

MAPLE

a:=proc(k) local k2: k2:=convert(k^3, base, 2): if add(k2[j], j=1..nops(k2)) mod 2=0 then k^3 else fi end: seq(a(k), k=1..70); # Emeric Deutsch, Jan 01 2007

isA001969 := proc(n) local b2 ; b2 := convert(n, base, 2) ; if sum(op(i, b2), i=1..nops(b2)) mod 2 = 0 then RETURN(true) ; else RETURN(false) ; fi ; end : for n from 1 to 80 do if isA001969(n^3) then printf("%d, ", n^3) ; fi ; od ; # R. J. Mathar, Jan 07 2007

MATHEMATICA

Select[Range[0, 55]^3, EvenQ @ DigitCount[#, 2][[1]] &] (* Amiram Eldar, Dec 09 2019 *)

CROSSREFS

Intersection of A000578 (cubes) and A001969 (evil numbers).

Sequence in context: A145555 A293894 A137800 * A179145 A118092 A126272

Adjacent sequences:  A125494 A125495 A125496 * A125498 A125499 A125500

KEYWORD

base,nonn

AUTHOR

Tanya Khovanova, Dec 27 2006

EXTENSIONS

More terms from Emeric Deutsch, Jan 01 2007

More terms from R. J. Mathar, Jan 07 2007

a(1) = 0 inserted by Amiram Eldar, Dec 09 2019

STATUS

approved

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Last modified July 8 22:01 EDT 2020. Contains 335537 sequences. (Running on oeis4.)