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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 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: 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 STATUS approved

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Last modified June 26 04:11 EDT 2019. Contains 324369 sequences. (Running on oeis4.)