%I #14 Jan 01 2021 11:38:25

%S 6,8,12,14,21,22,28,33,36,44,54,58,72,77,87,94,116,126,141,152,188,

%T 198,203,228,246,304,319,329,369,398,492,517,522,532,597,644,796,836,

%U 846,861,966,1042,1288,1353,1363,1368,1393,1563,1686,2084,2189,2204,2214

%N Products of two distinct Lucas numbers (2,3,4,7,11,18,...).

%H Robert Israel, <a href="/A274349/b274349.txt">Table of n, a(n) for n = 1..10000</a>

%e 6 = 2*3, 44 = 4*11.

%p N:= 10000: # for terms <= N

%p L:= gfun:-rectoproc({f(n)=f(n-1)+f(n-2),f(0)=2,f(1)=1},f(n),remember):

%p S:= {}:

%p for i from 2 do

%p u:= L(i);

%p if u > N then break fi;

%p for j from 0 to i-1 do

%p if j = 1 then next fi;

%p v:= u*L(j);

%p if v > N then break fi;

%p S:= S union {v};

%p od od:

%p sort(convert(S,list)); # _Robert Israel_, Jan 01 2021

%t z = 100; f[n_] := LucasL[n]; f[1] = 2 ;

%t Take[Sort[Flatten[Table[f[u] f[v], {u, 1, z}, {v, 1, u - 1}]]], z]

%t Take[Times@@@Subsets[Join[{2},LucasL[Range[2,20]]],{2}]//Union,60] (* _Harvey P. Dale_, Aug 13 2019 *)

%Y Cf. A000032, A274348, A274347, A271354.

%K nonn,easy

%O 1,1

%A _Clark Kimberling_, Jun 18 2016