Does there exist a closed form expression for the following sum:
Sum over n from 0 to infinity of:
Sin((2n+1)(pi)(a))/((pi)(2n+1))^(2k+3),
where a is a real number from 0 to 1, and k is an integer that is equal to or greater than 0.
I am looking for an answer only in terms of (a) and numerical constants.
I used Mathematica 12.3 to evaluate this sum, but the answer given was a rewrite of the sum.
If anyone knows of Tables of Sums or other sources where this sum is listed, please let me know.
Thanks very much for you kind help.