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%I A260384 #27 Jul 30 2015 10:26:15
%S A260384 6,16,44,122,268,556,886,1446,1964,2900
%N A260384 Maximal gap between successive elements of Pn with n >= 3. Pn : primes p <= A002110(n) such that q=2*A002110(n)-p is prime. (p, q) is a pair of centered primes at n-th primorial.
%e A260384 For n=3, primorial(3)=A002110(3) is 30 and P3 is (7, 13, 17, 19, 23, 29) because (53, 47, 43, 41, 37, 31) are all prime. The maximum gap between two consecutive terms of P3 is 6, obtained for (7,13) or (23,29), so a(3)=6.
%o A260384 (PARI) lstp(n)=my(v = []); pn = prod(i=1, n, prime(i)); forprime(p=1, pn-1, if (isprime(2*pn-p), v = concat(v, p))); my(w = vector(#v-1, k, v[k+1] - v[k])); vecmax(w); \\ _Michel Marcus_, Jul 24 2015
%o A260384 (PARI) a(n)=my(P=2*prod(i=1,n,prime(i)),r,last=P); forprime(p=2,P/2, if(isprime(P-p), r=max(r,p-last); last=p)); r \\ _Charles R Greathouse IV_, Jul 24 2015
%Y A260384 Cf. A002110.
%K A260384 nonn,more
%O A260384 3,1
%A A260384 _Jean-Marc Rebert_, Jul 24 2015
%E A260384 a(10) from _Charles R Greathouse IV_, Jul 24 2015
%E A260384 a(11) from _Charles R Greathouse IV_, Jul 28 2015
%E A260384 a(12) from _Charles R Greathouse IV_, Jul 30 2015

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