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A137250
Decimal expansion of the constant sum 1/(q*log(q)), summed over prime powers q > 1.
1
2, 0, 0, 6, 6, 6, 6, 4, 5, 2, 8, 3, 1, 0, 6, 8, 7, 5, 6, 4, 3, 2, 2, 9, 6, 9, 9, 9, 4, 7, 1, 3, 5, 8, 2, 0, 8, 4, 8, 8, 6, 8, 3, 5, 4, 1, 4, 7, 5, 0, 4, 5, 7, 8, 0, 5, 9, 0, 5, 4, 9, 8, 2, 7, 8, 2, 7, 4, 7, 8, 2, 1, 9, 2, 1, 6, 4, 7, 0, 5, 5, 0, 3, 1, 8, 4, 3, 8, 1, 7, 5, 9, 2, 0, 1, 5, 6, 1, 0, 1, 3, 0, 7, 9, 6
OFFSET
1,1
COMMENTS
Evaluated from Sum_{m,k >= 1} A008683(k)*I(k*m)/k^2, where I(x) = Integral_{t=x..infinity} log zeta(t) dt is Cohen's underivative.
REFERENCES
Henri Cohen, Number Theory, Volume II: Analytic and Modern Tools, GTM Vol. 240, Springer, 2007; see pp. 208-209.
FORMULA
Equals Sum_{n>=2} 1/(A000961(n)*log(A000961(n))).
Equals Sum_{p primes} -log(1-1/p)/log(p). - Vaclav Kotesovec, Jun 12 2022
EXAMPLE
2.0066664528310687...
PROG
(PARI) default(realprecision, 200); su = 0; for(s=1, 400, su = su + sum(k=1, 500, moebius(k)/k^2 * intnum(x=s*k, [[1], 1], log(zeta(x))))/s; print(su)); \\ Vaclav Kotesovec, Jun 12 2022
CROSSREFS
Sequence in context: A231063 A295216 A230250 * A329290 A244133 A378495
KEYWORD
nonn,cons
AUTHOR
R. J. Mathar, Mar 09 2008
EXTENSIONS
8 more digits from R. J. Mathar, Dec 04 2008
More terms from Vaclav Kotesovec, Jun 12 2022
STATUS
approved