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A372339
Decimal expansion of Sum_{k>=0} (-1)^k * (k+2) / ((k+1)*(2*k)!).
3
1, 3, 0, 3, 8, 4, 8, 8, 8, 7, 2, 2, 0, 2, 1, 2, 1, 6, 5, 5, 0, 7, 8, 1, 4, 4, 6, 5, 5, 8, 9, 5, 2, 7, 8, 1, 0, 4, 4, 2, 0, 5, 7, 3, 8, 3, 4, 5, 0, 5, 0, 8, 8, 1, 4, 3, 5, 5, 7, 9, 5, 1, 8, 6, 1, 2, 7, 1, 2, 1, 9, 9, 3, 1, 0, 5, 8, 9, 4, 6, 3, 1, 4, 5, 1, 1
OFFSET
1,2
FORMULA
Equals -2 + 3*cos(1) + 2*sin(1).
EXAMPLE
1.3038488872202121655078144655895278104420573...
MATHEMATICA
s = Sum[(-1)^k (k + 2)/((k + 1) (2 k)!), {k, 0, Infinity}]
d = N[s, 100]
First[RealDigits[d]]
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Apr 28 2024
STATUS
approved