A274792 - OEIS

A274792

a(n) = smallest prime p(1) in a symmetrical constellation of n consecutive twin primes: p(1), p(1)+2, ..., p(n), p(n)+2.

%I #28 Jul 27 2016 22:33:02

%S 3,5,5,663569,3031329797,17479880417,1855418882807417,2640138520272677

%N a(n) = smallest prime p(1) in a symmetrical constellation of n consecutive twin primes: p(1), p(1)+2, ..., p(n), p(n)+2.

%H N. Makarova and C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_813.htm">Symmetrical compositions of consecutive twin primes</a>.

%e The list of two consecutive twin primes (5, 7, 11, 13) is symmetrical because 5+13 = 7+11. Thus a(2) = 5.

%e The list of three consecutive twin primes (5, 7, 11, 13, 17, 19) is symmetrical because 5+19 = 7+17 = 11+13. Thus a(3) = 5.

%Y Cf. A077800.

%K nonn,more

%O 1,1

%A _Natalia Makarova_, Jul 07 2016

%E a(7)-a(8) from _Dmitry Petukhov_, Jul 07 2016