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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 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..97.

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

Adjacent sequences:  A132818 A132819 A132820 * A132822 A132823 A132824

KEYWORD

cons,nonn

AUTHOR

Cino Hilliard, Nov 17 2007

EXTENSIONS

Offset corrected R. J. Mathar, Jan 26 2009

STATUS

approved

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Last modified November 25 14:47 EST 2020. Contains 338625 sequences. (Running on oeis4.)