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Products of two distinct numbers that are the average of a pair of twin primes.
1

%I #17 Jun 23 2017 08:19:28

%S 24,48,72,108,120,168,180,216,240,252,288,360,408,432,504,540,552,600,

%T 612,648,720,756,768,792,828,864,900,912,960,1080,1128,1152,1188,1224,

%U 1248,1260,1296,1368,1392,1440,1620,1656,1680,1692,1728,1800,1836,1848

%N Products of two distinct numbers that are the average of a pair of twin primes.

%e 4 and 12 are two distinct numbers that are averages of twin prime pairs (i.e., 4 = (3+5)/2 and 12 = (11+13)/2), and 4*12 = 48, which is in the sequence.

%t m = 1 + Select[Range@1000, PrimeQ[#] && PrimeQ[# + 2] &]; Select[v Union@ Flatten@ Table[m[[i]] m[[j]], {i, Length[m]}, {j, i - 1}], # <= 4000 &] (* _Giovanni Resta_, Jun 13 2017 *)

%Y Cf. A014574, A249628.

%Y Subset of A286195.

%K nonn

%O 1,1

%A _Wesley Ivan Hurt_, Jun 12 2017

%E More terms from _Giovanni Resta_, Jun 13 2017