OFFSET
1,2
FORMULA
a(n) = floor(S*n^2), where S = Sum_{k>=1} 1/a(k).
EXAMPLE
a(10) = 147 because a(10) = floor(S*10^2), where S = 1/1 + 1/5 + 1/13 + 1/23 + 1/36 + 1/52 + 1/72 +... + 1/a(k) +... {k=1..inf}.
S = 1.471869231468455847281... This should be good to about 20 digits. - David Einstein
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul D. Hanna, Sep 08 2002
STATUS
approved