OFFSET
0,2
COMMENTS
See A210000 for a guide to related sequences.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 0..10000
MATHEMATICA
a = 0; b = n; z1 = 45;
t[n_] := t[n] = Flatten[Table[w + z - w*z + x*y, {w, a, b}, {x, a, b}, {y, a, b}, {z, a, b}]]
c[n_, k_] := c[n, k] = Count[t[n], k]
Table[c[n, 0], {n, 0, z1}] (* A210286 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Mar 19 2012
STATUS
approved