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A132821
Decimal expansion of the convergent to the sum of (1/9)^p where p ranges over the set of prime numbers.
1
0, 1, 3, 7, 3, 4, 5, 6, 5, 3, 2, 0, 0, 5, 4, 9, 1, 9, 2, 4, 3, 1, 4, 7, 1, 7, 5, 4, 0, 8, 6, 2, 5, 4, 5, 1, 6, 5, 0, 4, 4, 6, 8, 7, 7, 0, 2, 3, 0, 8, 3, 6, 5, 6, 6, 2, 9, 7, 2, 5, 2, 5, 5, 7, 0, 1, 5, 3, 1, 9, 1, 1, 3, 3, 8, 5, 0, 0, 8, 1, 0, 9, 3, 2, 2, 2, 8, 9, 1, 3, 7, 0, 7, 3, 9, 7, 9, 3
OFFSET
0,3
FORMULA
Equals 8 * Sum_{k>=1} pi(k)/9^(k+1), where pi(k) = A000720(k). - Amiram Eldar, Aug 11 2020
EXAMPLE
0.0137345...
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, A132799 (base 8), A010051 (base 10).
Sequence in context: A111383 A195769 A021968 * A247217 A252734 A101636
KEYWORD
cons,nonn
AUTHOR
Cino Hilliard, Nov 17 2007
EXTENSIONS
Offset corrected R. J. Mathar, Jan 26 2009
STATUS
approved