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A360166
Decimal expansion of sech(Pi).
0
8, 6, 2, 6, 6, 7, 3, 8, 3, 3, 4, 0, 5, 4, 4, 1, 4, 6, 9, 6, 5, 5, 4, 0, 4, 6, 3, 3, 1, 3, 3, 6, 8, 0, 3, 9, 1, 3, 9, 1, 9, 4, 0, 1, 8, 5, 7, 3, 6, 3, 6, 7, 8, 0, 7, 7, 4, 0, 1, 9, 7, 8, 3, 5, 2, 6, 4, 8, 8, 0, 2, 1, 5, 7, 7, 0, 3, 5, 8, 5, 7, 3, 1, 9, 7, 4, 3, 8, 8, 1, 8, 4, 2, 5, 7, 4, 1, 0, 6, 1, 7, 7, 6
OFFSET
-1,1
FORMULA
Equals 1/cosh(Pi).
Equals 2/A175314.
Equals (2*e^Pi)/(e^(2*Pi) + 1).
Equals Sum_{k>=0} 2*e^((i - 2)k*Pi - Pi).
Equals lim_{n->oo} (-2*e^(Pi - 2*Pi*n))*(e^(i*Pi*n) - e^(2*Pi*n))/(e^(2*Pi) + 1).
EXAMPLE
0.086266738334054414696554046331336803913919401857363678077401978352...
MATHEMATICA
RealDigits[Sech[Pi], 10, 105][[1]]
CROSSREFS
Cf. A175314.
Sequence in context: A021847 A029684 A200626 * A197732 A224237 A199785
KEYWORD
cons,nonn
AUTHOR
Wolfe Padawer, Jan 28 2023
STATUS
approved