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A027706 n-th prime has odd number of 1's in binary expansion and (n+1)st prime has even number of 1's. 2
1, 6, 8, 13, 15, 19, 22, 25, 29, 33, 37, 44, 54, 58, 61, 63, 65, 67, 73, 75, 78, 86, 88, 90, 95, 98, 100, 104, 107, 113, 116, 121, 123, 130, 132, 136, 138, 140, 145, 149, 151, 153, 158, 164, 169, 172, 175, 177, 181, 186, 189, 193, 198, 202, 205, 207, 210, 212, 220 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..2600

MATHEMATICA

c[ n_ ] := OddQ[ Count[ IntegerDigits[ n, 2 ], 1 ] ]; Select[ Range[ 500 ], c[ Prime[ # ] ]&&Not[ c[ Prime[ #+1 ] ] ]& ]

SequencePosition[Table[If[OddQ[DigitCount[n, 2, 1]], 1, 0], {n, Prime[Range[ 300]]}], {1, 0}][[All, 1]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 01 2019 *)

CROSSREFS

Cf. A027705 (corresponding primes).

Cf. A027702, A027704, A027708.

Sequence in context: A160133 A057710 A285678 * A047336 A181449 A315874

Adjacent sequences:  A027703 A027704 A027705 * A027707 A027708 A027709

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Erich Friedman

Offset changed by Michel Marcus, Mar 29 2018

STATUS

approved

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Last modified December 7 05:14 EST 2019. Contains 329839 sequences. (Running on oeis4.)