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A166007
Number of ones in the binary representation of the middle member q of the prime triple (p,q,r) with p<q<r=p+6.
1
3, 3, 3, 2, 3, 3, 4, 4, 4, 5, 5, 5, 3, 4, 5, 5, 4, 6, 5, 6, 6, 7, 5, 4, 7, 7, 6, 7, 6, 7, 4, 4, 9, 5, 6, 6, 6, 7, 7, 8, 6, 5, 5, 5, 9, 8, 6, 7, 8, 9, 4, 5, 6, 8, 7, 6, 6, 9, 4, 7, 7, 8, 7, 7, 6, 7, 7, 7, 7, 7, 9, 8, 3, 6, 6, 7, 7, 7, 7, 6, 7, 8, 6, 6, 5, 8
OFFSET
1,1
LINKS
EXAMPLE
For n = 3, (p, q, r) = (11, 13, 17), q = 13
Decimal 13 = Binary 1101
a(3) = Number of ones in 1101 = 3
MATHEMATICA
DigitCount[#, 2, 1]&/@Transpose[Select[Partition[Prime[Range[1000]], 3, 1], Last[#]-First[#]==6&]][[2]] (* Harvey P. Dale, Dec 03 2014 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Steven Lubars (lubars(AT)gmail.com), Oct 03 2009
EXTENSIONS
More terms from Harvey P. Dale, Dec 03 2014
STATUS
approved