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A132799
Decimal expansion of the convergent to the sum of (1/8)^p where p ranges over the set of prime numbers.
2
0, 1, 7, 6, 0, 9, 1, 1, 9, 5, 3, 3, 5, 1, 7, 9, 6, 5, 3, 8, 5, 2, 7, 8, 4, 9, 7, 3, 5, 6, 6, 3, 1, 3, 4, 2, 6, 2, 3, 8, 1, 8, 1, 8, 0, 1, 0, 7, 9, 4, 9, 6, 9, 9, 4, 0, 6, 4, 8, 0, 1, 2, 6, 8, 4, 1, 2, 8, 7, 5, 4, 9, 4, 1, 2, 3, 2, 1, 4, 4, 4, 7, 2, 5, 7, 5, 7, 7, 3, 6, 2, 4, 6, 3, 2, 1, 9, 6
OFFSET
0,3
FORMULA
Equals 7 * Sum_{k>=1} pi(k)/8^(k+1), where pi(k) = A000720(k). - Amiram Eldar, Aug 11 2020
EXAMPLE
0.01760911...
PROG
(PARI) /* Sum of 1/m^p for primes p */ sumnp(n, m) = { local(s=0, a, j); for(x=1, n, s+=1./m^prime(x); ); a=Vec(Str(s)); for(j=3, n, print1(eval(a[j])", ") ) }
CROSSREFS
Cf. A000720, A132822 (base 7), A132821 (base 9).
Sequence in context: A111764 A194348 A094123 * A154580 A256319 A324688
KEYWORD
cons,nonn
AUTHOR
Cino Hilliard, Nov 17 2007
EXTENSIONS
Offset corrected R. J. Mathar, Jan 26 2009
STATUS
approved