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A125497 Evil cubes. 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

1,1

LINKS

Table of n, a(n) for n=1..36.

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

CROSSREFS

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

Sequence in context: A275430 A145555 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

STATUS

approved

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Last modified April 28 16:04 EDT 2017. Contains 285578 sequences.