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A271499 Positive numbers n such that the number of 1's in the binary expansion of n is not a power of 2. 2
7, 11, 13, 14, 19, 21, 22, 25, 26, 28, 31, 35, 37, 38, 41, 42, 44, 47, 49, 50, 52, 55, 56, 59, 61, 62, 63, 67, 69, 70, 73, 74, 76, 79, 81, 82, 84, 87, 88, 91, 93, 94, 95, 97, 98, 100, 103, 104, 107, 109, 110, 111, 112, 115, 117, 118, 119, 121, 122, 123, 124, 125, 126, 127, 131, 133, 134, 137, 138, 140 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Michel Marcus, Table of n, a(n) for n = 1..10000

EXAMPLE

127 = 1111111_2 has seven 1's, so is a term (this distinguishes the sequence from A235336).

MATHEMATICA

Select[Range@ 140, ! IntegerQ@ Log2@ First@ DigitCount[#, 2] &] (* Michael De Vlieger, Apr 16 2016 *)

PROG

(PARI) lista(nn) = {for (n=1, nn, my(nbd = hammingweight(n)); if (!((nbd==1) || (nbd==2) || (ispower(nbd, , &k) && (k==2))), print1(n, ", ")); ); } \\ Michel Marcus, Apr 16 2016

(Python)

A271499_list = [n for n in range(1, 10**6) if bin(bin(n).count('1')).count('1') != 1] # Chai Wah Wu, Apr 16 2016

CROSSREFS

Complement of A143071.

Similar to but different from A075930, A235336 and A271500.

Sequence in context: A119393 A155501 A271500 * A235336 A075930 A014311

Adjacent sequences:  A271496 A271497 A271498 * A271500 A271501 A271502

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Apr 16 2016

STATUS

approved

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Last modified December 16 07:41 EST 2017. Contains 296076 sequences.