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A102534
Number of distinct values of i*j + j*k + k*i with 1 <= i<= j < k <= n.
4
0, 1, 4, 10, 19, 33, 49, 70, 96, 127, 161, 201, 238, 287, 337, 390, 449, 519, 586, 662, 741, 818, 902, 997, 1095, 1194, 1299, 1410, 1518, 1651, 1778, 1908, 2054, 2186, 2332, 2493, 2636, 2793, 2955, 3128, 3300, 3481, 3660, 3840, 4050, 4252, 4443, 4665, 4871
OFFSET
1,3
LINKS
MAPLE
F:= proc(n) local i, j;
{seq(seq(i*j + (i+j)*n, i=1..j), j=1..n-1)}
end proc:
R:= NULL:
S:= {}:
for n from 1 to 100 do
S:= S union F(n);
R:= R, nops(S);
od:
R; # Robert Israel, Dec 15 2024
MATHEMATICA
f[n_] := Length[ Union[ Flatten[ Table[i*j + j*k + k*i, {i, n}, {j, i, n}, {k, j + 1, n}]]]]; Table[ f[n], {n, 48}] (* Robert G. Wilson v, Jan 13 2005 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Jan 13 2005
STATUS
approved