|
|
A060773
|
|
Numbers having a unique partition into three nonnegative triangular numbers.
|
|
9
|
|
|
0, 1, 2, 4, 5, 8, 11, 14, 20, 29, 50, 53
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
LINKS
|
|
|
MATHEMATICA
|
trig[n_]:=n(n+1)/2; trigInv[x_]:=Ceiling[Sqrt[Max[0, 2x]]]; lim=100; nLst=Table[0, {trig[lim]}]; Do[n=trig[a]+trig[b]+trig[c]; If[n>0 && n<=trig[lim], nLst[[n]]++ ], {a, 0, lim}, {b, a, trigInv[trig[lim]-trig[a]]}, {c, b, trigInv[trig[lim]-trig[a]-trig[b]]}]; Flatten[Position[nLst, 1]] (T. D. Noe, Aug 10 2005)
|
|
CROSSREFS
|
Cf. A111638 (n having a unique partition into three positive triangular numbers).
|
|
KEYWORD
|
nonn,fini,full
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|