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A085108
Decimal expansion of sum 1/(p*2^p) where p runs through the set of Artin primes (primes with primitive root 2).
1
0, 4, 7, 9, 7, 0, 5, 4, 6, 3, 4, 6, 4, 4, 6, 5, 2, 3, 4, 8, 8, 2, 8, 7, 3, 0, 9, 9, 8, 0, 9, 4, 7, 3, 2, 3, 2, 0, 5, 8, 2, 4, 5, 4, 0, 3, 1, 3, 0, 4, 0, 4, 3, 0, 4, 8, 3, 3, 9, 8, 2, 3, 2, 0, 4, 5, 1, 7, 2, 1, 2, 9, 2, 9, 4, 9, 9, 1, 0, 1, 7, 4, 4, 7, 8, 4, 8, 7, 9, 0, 3, 7, 7, 1, 3, 0, 0, 7, 6, 7, 7, 5, 0, 1
OFFSET
0,2
COMMENTS
David H. Bailey and Richard E. Crandal conjectured that this constant is 2-normal.
REFERENCES
David H. Bailey and Richard E. Crandall, Random Generators and Normal Numbers, 2000
FORMULA
c=0.0479705463464....
MATHEMATICA
Join[{0}, RealDigits[Total[1/(# 2^#)&/@Select[Prime[Range[100]], PrimitiveRoot[ #, 2]==2&]], 10, 120][[1]]] (* Harvey P. Dale, Apr 02 2018 *)
PROG
(PARI) sum(k=1, 2000, if(znprimroot(prime(k))-2, 0, 1)*1./prime(k)/2^prime(k))
CROSSREFS
Sequence in context: A371525 A105169 A200618 * A106502 A046254 A268227
KEYWORD
cons,nonn
AUTHOR
Benoit Cloitre, Aug 10 2003
STATUS
approved