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A285832
Decimal expansion of the total area of a standard phugoid.
0
1, 6, 9, 0, 9, 7, 6, 6, 6, 3, 9, 6, 9, 0, 0, 1, 8, 3, 3, 7, 2, 1, 6, 4, 6, 9, 8, 2, 7, 8, 1, 1, 9, 6, 9, 6, 6, 2, 1, 4, 1, 6, 9, 5, 8, 4, 2, 0, 4, 5, 1, 7, 2, 7, 4, 7, 0, 5, 6, 5, 2, 4, 0, 9, 6, 5, 9, 4, 8, 0, 4, 9, 4, 2, 9, 8, 1, 8, 3, 4, 7, 9, 4, 3, 9, 3, 1, 0, 8, 8, 9, 6, 6, 2, 7, 7, 5, 2, 9, 4, 8, 3, 9, 7, 9
OFFSET
1,2
COMMENTS
The curve crosses the x-axis at (4k-1)/4*Pi.
FORMULA
Sum_{n=0..inf} (-1)^n * Integral_{x=(4n-1)*Pi/4..(4n+3)*Pi/4} (cos(x) + sin(x))/e^x.
EXAMPLE
1.690976663969001833721646982781196966214169584204517274705652409659480494298183...
MATHEMATICA
Sum[(-1)^n*NIntegrate[ Exp[-x] (Cos[x] + Sin[x]), {x, (4n -1)Pi/4, (4n +3)Pi/4}, AccuracyGoal -> 128, PrecisionGoal -> 128, WorkingPrecision -> 156], {n, 0, 115}]
(* to view the curve *) Plot[Exp[-x] (Cos[x] + Sin[x]), {x, -3/4 Pi, 11/4 Pi}]
CROSSREFS
Sequence in context: A298517 A199451 A135154 * A187798 A371321 A339802
KEYWORD
nonn,cons
AUTHOR
Robert G. Wilson v, Apr 27 2017
STATUS
approved