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A371721
Numbers representable in the form u*v*(u+v) for u >= v >= 0 in at least two ways.
2
0, 30, 210, 240, 390, 420, 462, 810, 880, 1008, 1020, 1056, 1122, 1190, 1482, 1680, 1920, 1980, 2070, 2100, 2310, 2970, 3120, 3360, 3696, 3750, 4160, 4290, 4320, 4830, 4914, 5460, 5670, 6006, 6090, 6270, 6480, 6630, 7040, 7380, 7440, 7770, 8064, 8160, 8190, 8448, 8580, 8976, 9120, 9240, 9520, 9900, 10290, 10530, 10640, 11340, 11856, 12210, 12432, 12474, 13110
OFFSET
1,2
LINKS
MAPLE
N:= 10^5: # for terms <= N
V:= Vector(N):
for v from 1 while 2*v^3 <= N do
for u from v do
x:= u*v*(u+v);
if x > N then break fi;
V[x]:= V[x]+1
od od:
[0, op(select(t -> V[t] >= 2, [$1..N]))]; # Robert Israel, Dec 15 2024
CROSSREFS
Subsequence of A088915.
Sequence in context: A209796 A209789 A280482 * A203617 A181629 A346245
KEYWORD
nonn
AUTHOR
Max Alekseyev, Apr 04 2024
STATUS
approved