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A242597
One half of the denominators of the partial sums of dilog(1/2).
1
1, 8, 72, 1152, 28800, 4800, 117600, 30105600, 812851200, 812851200, 98354995200, 393419980800, 66487976755200, 33243988377600, 8310997094400, 17020922049331200, 4919046472256716800, 1639682157418905600, 591925258828224921600, 295962629414112460800, 295962629414112460800
OFFSET
1,2
COMMENTS
The numerator sequence is A242596. See the comment there for details and the Abramowitz-Stegun link and the Jolley reference.
FORMULA
a(n) = denominator(r(n))/2 with the rational r(n) := sum(1/(k^2*2^k), k=1..n) in lowest terms.
EXAMPLE
r(10^k), for k=1..3: .5000000000, .5822335189, .5822405265, .5822405265 (maple 10 digits). To be compared with the limit 0.58224052646... given in A076788.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Wolfdieter Lang, Jun 16 2014
STATUS
approved