OFFSET
1,2
MATHEMATICA
a = {}; d = {}; e = {-1}; Do[b = {}; c = {}; Do[If[k > 0, AppendTo[b, k]]; AppendTo[c, n - k], {k, 0, n}] ; AppendTo[a, FromDigits[b, n + 1]]; AppendTo[d, FromDigits[c, n + 1]], {n, 1, 30}]; Do[AppendTo[e, d[[n]] - a[[n + 1]]], {n, 1, 29}]; e
CROSSREFS
KEYWORD
sign
AUTHOR
Artur Jasinski, Nov 08 2007, Nov 10 2007
STATUS
approved