A102534 Number of distinct values of i*j + j*k + k*i with 1 <= i<= j < k <= n.

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

Author

Robert G. Wilson v, Jan 13 2005

Keywords

• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..2000

Crossrefs

Cf. A100439, A100440, A102533.

Programs

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 *)