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A209050
Pyramid angle = arccos(1/sqrt(e)) in radians.
0
9, 1, 9, 1, 0, 6, 6, 5, 7, 2, 9, 3, 5, 8, 8, 4, 2, 2, 0, 4, 1, 3, 6, 1, 7, 1, 4, 8, 9, 6, 7, 4, 2, 7, 0, 5, 7, 5, 5, 6, 3, 0, 7, 3, 4, 0, 2, 0, 3, 5, 1, 1, 4, 7, 3, 9, 8, 5, 0, 9, 2, 4, 2, 8, 1, 5, 7, 5, 1, 3, 5, 6, 8, 3, 9, 3, 1, 3, 7, 2, 7, 1, 5, 1, 5, 1, 6, 4, 0, 4, 3, 4, 5, 1, 5, 8, 8, 8, 1, 9, 8, 7, 1, 2, 2, 1, 5, 8, 3, 0, 3
OFFSET
0,1
FORMULA
arccos(1/sqrt(e)) = arccos(1/sqrt(A001113)) = arccos(1/A019774) = arccos(A092605).
EXAMPLE
= 0.91910665729358842204136171489674270575563073402035114...
= 52°.660932385299557203750879574284228798519442622806897...
= 52°39'.655943117973432225052774457053727911166557368413...
= 52°39'39.3565870784059335031664674232236746699934421048..."
MATHEMATICA
RealDigits[ ArcCos[ 1/Sqrt[ E]], 10, 111][[1]]
PROG
(PARI) acos(exp(-1/2)) \\ Charles R Greathouse IV, Mar 05, 2012
CROSSREFS
KEYWORD
nonn,easy,cons
AUTHOR
Robert G. Wilson v, Mar 04 2012
STATUS
approved