A047975 - OEIS

%I #3 Mar 31 2012 13:50:35

%S 2,4,2,4,6,6,4,2,4,4,2,6,4,6,4,4,6,4,2,2,4,2,4,6,6,10,8,4,4,4,2,4,4,2,

%T 6,6,4,2,8,6,12,2,2,8,10,2,12,6,4,4,14,2,18,16,6,10,4,8,4,2,8,12,2,8,

%U 12,10,6,2,6

%N Let (p1,p2), (p3,p4) be two pairs of successive primes such that p1*p2=p3+p4-1, |p2-p1|=|p4-p3|; sequence gives |p2-p1|=|p4-p3|.

%e E.g 5*7=17+19-1,(7-5=19-17=2); 7*11=37+41-1,(11-7=41-37=4); 11*13=71+73-1,(13-11=73-71=2); 13*17=109+113-1,(17-13=113-109=4);...

%K nonn

%O 0,1

%A _Naohiro Nomoto_