Ec primes are primes of the form:
$(2^n-1)\cdot 10^d+2^{n-1}-1$, where d Is the Number of decimal digits of $2^{n-1}$.
n's leading to a prime are contained in the following bector:
$2,3,4,7,8,12,19,22,36,46,51,67,79,215,359,394,451,1323$
Now I call a(1)=2,a(2)=3,a(3)=4,...a(j) the j-th component of the Vector of n's leading to a prime.
Is It Just a coincidence that
$a(18)+1=a(1)+a(2)+...+a(16)$?
From here can be derived some recurrence relation or Is It Just a trivial relation?
Is there $a(j)>1323$ such that $a(j)+1=a(1)+a(2)+...+a(j-2)$?