OFFSET
1,4
LINKS
Eric Weisstein's World of Mathematics, Angle Trisection
EXAMPLE
x/3 + x^3/648 + x^5/31104 + (7*x^7)/11197440 + (443*x^9)/40633270272 + ...
CROSSREFS
KEYWORD
sign,frac
AUTHOR
Eric W. Weisstein, Mar 22 2009
STATUS
approved