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A027707 Primes with odd number of 1's in binary expansion such that next prime also has odd number of 1's. 1
7, 11, 31, 37, 59, 61, 73, 103, 107, 127, 131, 151, 167, 173, 179, 181, 191, 199, 211, 223, 227, 229, 233, 239, 241, 409, 419, 421, 431, 433, 439, 487, 491, 557, 563, 577, 601, 607, 613, 631, 647, 653, 659, 701, 709, 719, 727, 757, 761, 823, 827, 911, 919 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Table of n, a(n) for n=0..52.

MATHEMATICA

c[ n_ ] := OddQ[ Count[ IntegerDigits[ n, 2 ], 1 ]]; Map[ Prime, Select[ Range[ 200 ], c[ Prime[ # ]]&&c[ Prime[ #+1 ]]& ]]

CROSSREFS

Sequence in context: A109907 A121534 A083363 * A046861 A078917 A291349

Adjacent sequences:  A027704 A027705 A027706 * A027708 A027709 A027710

KEYWORD

nonn

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Erich Friedman.

STATUS

approved

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Last modified December 14 14:50 EST 2019. Contains 329979 sequences. (Running on oeis4.)