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A052294
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Pernicious numbers: numbers with a prime number of 1's in their binary expansion.
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8
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3, 5, 6, 7, 9, 10, 11, 12, 13, 14, 17, 18, 19, 20, 21, 22, 24, 25, 26, 28, 31, 33, 34, 35, 36, 37, 38, 40, 41, 42, 44, 47, 48, 49, 50, 52, 55, 56, 59, 61, 62, 65, 66, 67, 68, 69, 70, 72, 73, 74, 76, 79, 80, 81, 82, 84, 87, 88, 91, 93, 94, 96, 97, 98, 100
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OFFSET
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1,1
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COMMENTS
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If a prime p is of the form 2^k -1, then p is included in this sequence. [From Leroy Quet Sep 20 2008]
There are A121497(n) n-bit members of this sequence. - Charles R Greathouse IV, Mar 22 2013
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LINKS
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T. D. Noe, Table of n, a(n) for n = 1..1000
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EXAMPLE
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No power of two is pernicious, but 2^n+1 always is.
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MATHEMATICA
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Select[Range[6! ], PrimeQ[DigitCount[ #, 2][[1]]]&] [From Vladimir Joseph Stephan Orlovsky, Feb 16 2010]
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PROG
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(Haskell)
a052294 n = a052294_list !! (n-1)
a052294_list = filter ((== 1) . a010051 . a000120) [1..]
-- Reinhard Zumkeller, Nov 16 2012
(PARI) is(n)=isprime(hammingweight(n)) \\ Charles R Greathouse IV, Mar 22 2013
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CROSSREFS
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Cf. A000069, A001969, A010051, A000120, A081092 (primes).
Sequence in context: A184987 A188916 A080943 * A191916 A182834 A116883
Adjacent sequences: A052291 A052292 A052293 * A052295 A052296 A052297
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KEYWORD
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easy,nice,nonn
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AUTHOR
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Jeremy Gow (jeremygo(AT)dai.ed.ac.uk), Feb 08 2000
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STATUS
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approved
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