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Number of pairs of odd numbers that separate two consecutive twin prime pairs
1

%I #9 Sep 04 2013 12:28:55

%S 0,2,2,5,5,8,5,14,2,14,5,14,5,2,14,5,14,5,14,17,35,5,14,29,23,14,8,11,

%T 8,74,5,2,14,11,68,5,8,5,14,29,38,23,5,5,8,53,11,14,2,59,5,23,14,11,

%U 32,41,2,26,8,23,14,26,2,11,8,5,47,14,20,14,20

%N Number of pairs of odd numbers that separate two consecutive twin prime pairs

%C Example: a(3) = 2 because the third twin prime pair is (11, 13) and there are two pairs of odd numbers between (11, 13) and its immediate predecessor, (5,7), namely (7, 9) and (9, 11).

%F a(n) = (A001359(n+1) - (A001359(n) + 2))/2 = (A001359(n+1) - A006512(n))/2. - _Michel Marcus_, Sep 04 2013

%o (PARI) lista(nn) = {prm = primes(nn); gtp = select(p->isprime(p-2), prm); ltp = select(p->isprime(p+2), prm); for (i=1, #ltp-1, print1((ltp[i+1] - gtp[i])/2, ", "););} \\ _Michel Marcus_, Sep 04 2013

%K nonn

%O 1,2

%A John Austin Curry (acurry(AT)mckoolsmith.com), Sep 30 2008

%E More terms from _Michel Marcus_, Sep 04 2013