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A125498 Odious cubes. 2
1, 8, 64, 512, 2197, 4096, 12167, 15625, 17576, 24389, 32768, 42875, 79507, 91125, 97336, 117649, 125000, 132651, 140608, 195112, 205379, 226981, 262144, 300763, 328509, 343000, 357911, 389017, 456533, 493039, 614125, 636056, 704969, 729000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

2197 is in the sequence because 2197=13^3 and 2197 in base 2 is 100010010101, having an odd number of 1's.

MAPLE

isA000069 := proc(n) local b2 ; b2 := convert(n, base, 2) ; if sum(op(i, b2), i=1..nops(b2)) mod 2 = 1 then RETURN(true) ; else RETURN(false) ; fi ; end : for n from 1 to 80 do if isA000069(n^3) then printf("%d, ", n^3) ; fi ; od ; # R. J. Mathar, Jan 07 2007

a:=proc(n) local n2: n2:=convert(n^3, base, 2): if sum(n2[j], j=1..nops(n2)) mod 2 = 1 then n^3 else fi end: seq(a(n), n=1..100); # Emeric Deutsch, Jan 10 2007

CROSSREFS

Intersection of A000578 (cubes) and A000069 (odious numbers).

Sequence in context: A126629 A250350 A171282 * A193539 A228739 A267730

Adjacent sequences:  A125495 A125496 A125497 * A125499 A125500 A125501

KEYWORD

base,nonn

AUTHOR

Tanya Khovanova, Dec 27 2006

EXTENSIONS

More terms from R. J. Mathar and Emeric Deutsch, Jan 07 2007

STATUS

approved

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Last modified August 21 17:29 EDT 2017. Contains 290891 sequences.