OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Square Triangle Picking
FORMULA
(3*2^(3 - n)*(1 + (2 + n)*HarmonicNumber[1 + n]))/((1 + n)*(2 + n)^3*(3 + n)^2).
EXAMPLE
1, 11/144, 1/96, 137/72000, 1/2400, 363/3512320, ...
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Eric W. Weisstein, Mar 26 2004; Jan 27 2005
STATUS
approved