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A371745 Decimal expansion of Sum_{k>=0} (-1)^k * k / ((k+1) (2k)!). 1
2, 2, 3, 2, 4, 4, 2, 7, 5, 4, 8, 3, 9, 3, 2, 7, 3, 0, 7, 0, 5, 9, 4, 1, 2, 5, 0, 7, 0, 3, 5, 7, 4, 6, 0, 2, 9, 7, 7, 4, 3, 6, 5, 4, 2, 2, 1, 4, 6, 6, 4, 3, 5, 9, 0, 1, 5, 6, 0, 0, 6, 7, 5, 3, 6, 4, 9, 2, 1, 2, 0, 3, 5, 5, 6, 9, 5, 1, 1, 0, 2, 4, 1, 5, 2, 3 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
FORMULA
Equals 2 - cos(1) - 2 sin(1).
EXAMPLE
-0.2232442754839327307059412507035746029774...
MATHEMATICA
s = Sum[(-1)^k k/((k + 1) (2 k)!), {k, 0, Infinity}]
d = N[s, 100]
First[RealDigits[d]]
CROSSREFS
Sequence in context: A175012 A051693 A266470 * A209700 A115980 A088936
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, May 01 2024
STATUS
approved

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Last modified July 12 17:45 EDT 2024. Contains 374251 sequences. (Running on oeis4.)