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A230048 Squarefree odious numbers. 1
1, 2, 7, 11, 13, 14, 19, 21, 22, 26, 31, 35, 37, 38, 41, 42, 47, 55, 59, 61, 62, 67, 69, 70, 73, 74, 79, 82, 87, 91, 93, 94, 97, 103, 107, 109, 110, 115, 118, 122, 127, 131, 133, 134, 137, 138, 143, 145, 146, 151, 155, 157, 158, 161, 167, 173, 174, 179, 181, 182, 185, 186, 191, 193, 194, 199 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Odious numbers that are squarefree numbers.

LINKS

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

MAPLE

with(numtheory); P:=proc(q) local n;

for n from 1 to q do if issqrfree(n) then

if type(add(a, a=convert(n, base, 2)), odd) then print(n);

fi; fi; od; end: P(10^3); # Paolo P. Lava, Oct 09 2013

MATHEMATICA

odiousQ[n_] := OddQ @ DigitCount[n, 2][[1]]; Select[Range[200], odiousQ[#] && SquareFreeQ[#] &] (* Amiram Eldar, Dec 10 2019 *)

PROG

(PARI) is(n)=hammingweight(n)%2 && issquarefree(n) \\ Charles R Greathouse IV, Mar 18 2014

CROSSREFS

Intersection of A000069 and A005117.

Sequence in context: A136734 A113544 A045173 * A201362 A063976 A064000

Adjacent sequences:  A230045 A230046 A230047 * A230049 A230050 A230051

KEYWORD

nonn,base

AUTHOR

Irina Gerasimova, Oct 06 2013

EXTENSIONS

Corrected by R. J. Mathar, Oct 06 2013

STATUS

approved

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Last modified January 24 13:11 EST 2022. Contains 350538 sequences. (Running on oeis4.)