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A095073 Primes in whose binary expansion the number of 1-bits is one more than the number of 0-bits. 3
5, 19, 71, 83, 89, 101, 113, 271, 283, 307, 313, 331, 397, 409, 419, 421, 433, 457, 1103, 1117, 1181, 1223, 1229, 1237, 1303, 1307, 1319, 1381, 1427, 1429, 1433, 1481, 1489, 1559, 1579, 1607, 1613, 1619, 1621, 1637, 1699, 1733, 1811, 1861 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Indranil Ghosh, Table of n, a(n) for n = 1..25000

A. Karttunen and J. Moyer, C-program for computing the initial terms of this sequence

EXAMPLE

71 is in the sequence because 71_10 = 1000111_2. '1000111' has four 1's and three 0's. - Indranil Ghosh, Feb 03 2017

MATHEMATICA

Select[Prime[Range[500]], Differences[DigitCount[#, 2]] == {-1} &]

PROG

(PARI)

{ forprime(p=2, 2000,

  v=binary(p); s=0;

  for(k=1, #v, s+=if(v[k]==1, +1, -1));

  if(s==1, print1(p, ", "))

) }

(Python)

from symy import isprime

i=1

j=1

while j<=25000:

....if isprime(i)==True and bin(i)[2:].count("1")-bin(i)[2:].count("0")==1:

........print str(j)+" "+str(i)

........j+=1

....i+=1 # Indranil Ghosh, Feb 03 2017

CROSSREFS

Intersection of A000040 and A031448. Subset of A095070. Cf. A095053.

Sequence in context: A026590 A243413 A222538 * A128349 A255449 A296630

Adjacent sequences:  A095070 A095071 A095072 * A095074 A095075 A095076

KEYWORD

nonn,base,easy

AUTHOR

Antti Karttunen, Jun 01 2004

STATUS

approved

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Last modified April 26 11:46 EDT 2019. Contains 322472 sequences. (Running on oeis4.)