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 A072570 Even interprimes i = (p+q)/2 (where p, q are consecutive primes) such that (q-p)/2 is not divisible by 3. 2

%I

%S 4,6,12,18,30,42,60,72,102,108,120,138,144,150,180,186,192,198,228,

%T 240,246,270,282,288,300,312,324,342,348,414,420,426,432,462,522,552,

%U 570,582,600,618,636,642,660,696,714,780,792,810,816,822,828,834,846,858

%N Even interprimes i = (p+q)/2 (where p, q are consecutive primes) such that (q-p)/2 is not divisible by 3.

%C A superset of A014574. [From _R. J. Mathar_, Mar 03 2009]

%F d = (P_n+1 - P_n)/2 is even & d == +/- 1 (mod 6).

%t a = Table[Prime[n], {n, 2, 200}]; b = {}; Do[d = (a[[n + 1]] - a[[n]])/2; If[ EvenQ[ a[[n]] + d] && (Mod[d, 6] == 5 || Mod[d, 6] == 1), b = Append[b, a[[n]] + d]], {n, 1, 198}]; b

%Y Cf. A024675, A072571. A072568 is union of A072571 and this sequence.

%K nonn

%O 1,1

%A _Marco Matosic_, Jun 24 2002

%E Edited by _N. J. A. Sloane_ and _Robert G. Wilson v_, Jun 27 2002

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