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%I #3 May 01 2013 21:05:52
%S 2,8,32,113,382,833,1822,3713,7582
%N The value of the sum shown in the display appears to 2, 8, 32 - sqrt(2), 113, 382, 833, 1822, 3713, 7582, ... for n = 1, ..., 9.
%C This is an unusual sequence mentioned on the Math Fun Mailing list. It does not quite fit the format of regular OEIS entries, but is too interesting to be forgotten. - _N. J. A. Sloane_, Mar 29 2009
%C The definition arises from the Fourier series for the Snowflake curve.
%C ..................................................................
%C .............................. inf ...............................
%C .............................. ==== ............ m ...............
%C ............................ k \ ....... %pi (k 2..- 5) ..... n ..
%C ....................... (- 1).. > .. tan(--------------) (- 1) ...
%C ............. inf ............ / ............ n + m ..............
%C ............. ==== ........... ==== ........ 2 ...................
%C ..... 5 m - 1 \ .............. n = 1 .............................
%C .. 3 2 ....... > ...... --------------------------------------- ..
%C ............. / .................................... m ...........
%C ............. ==== .......... m ... 3 ... 10 %pi (k 2 .- 5) ......
%C ............. k = - inf . (k 2..- 5)..csc(-----------------) .....
%C ................................................ 2 m .............
%C ............................................... 2 ................
%C .. ------------------------------------------------------------ ..
%C ........................... 3 ... 5 %pi ..........................
%C ........................ %pi..csc(-----) .........................
%C ................................... m ............................
%C .................................. 2 .............................
%K nonn
%O 1,1
%A _Bill Gosper_, Apr 12 2005
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