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A210617
Decimal expansion of infinite sum of cosines in second column of Schramm triangle.
0
4, 7, 9, 0, 8, 8, 2, 5, 7, 2, 7, 6, 5, 5, 2, 3, 4, 2, 6, 9, 1, 0, 6, 9, 6, 0, 2, 9, 5, 0, 5, 4, 7, 5, 7, 3, 3, 4, 3, 6, 6, 5, 5, 0, 1, 6, 2, 6, 7, 1, 1, 4, 6, 1, 8, 1, 0, 6, 2, 3, 3, 9, 8, 7, 6, 1, 6, 8, 9, 6, 5, 0, 0, 2, 8, 7, 8, 8, 0, 4, 2, 8, 3, 2, 8, 7, 1, 4, 9, 1, 6, 0, 4, 0, 6, 0, 9, 6, 1, 5, 2, 8, 6, 6, 8
OFFSET
0,1
COMMENTS
The Schramm triangle is the lower triangular part of the square array A191898 times Cos(k/n*2*Pi).
FORMULA
Equals Sum[Cos[2*Pi*2/(n + 0)]/(n + 0) - Cos[2*Pi*2/(n + 1)]/(n + 1), {n, 1, Infinity, 2}]
EXAMPLE
0.4790882572765523426...
MATHEMATICA
RealDigits[N[Sum[Cos[2*Pi*2/(n + 0)]/(n + 0) - Cos[2*Pi*2/(n + 1)]/(n + 1), {n, 1, Infinity, 2}], 90]][[1]]
CROSSREFS
Sequence in context: A141669 A190967 A004787 * A191762 A107905 A258707
KEYWORD
nonn,cons
AUTHOR
Mats Granvik, Mar 24 2012
EXTENSIONS
Offset corrected by and more terms from Rick L. Shepherd, Jan 07 2014
STATUS
approved