COMMENT from M. F. Hasler on A096502

[Maximilian Hasler]

In the following I suggest a new N-line.

%I A096502
%S A096502 2,3,3,39,4,4,4,5,6,5,5,6,5,5,5,7,6,6,11,7,6,29,6,6,7,6,6,7,6,6,6,8,8,7
%N A096502 Least exponent such that 2^a(n)-(2n+1) is prime, or 0 if no
such prime exists.
%C A096502 As D.W.Wilson observes, this is similar to the
Riesel/Sierpinski problem, and there is e.g. no prime of the form 2^k
- 777149, which is divisible by 3,5,7,13,19,37 or 73 if k is in 1+2Z,
2+4Z, 4+12Z, 8+12Z, 12+36Z, 0+36Z resp. 24+36Z.
Already for n=935 it is difficult to find a solution. Is this linked
to the fact that 2n+1=1871 is member of a prime quadruple (A007530)
and quintuple (A022007)?
%o A096502 (PARI) A096502(n,k)={ k | k=log(n)\log(2)+1; n=2*n+1;
while( !ispseudoprime(2^k++-n),);k } /* will take long for n=935... */
%K A096502 nonn
%O A096502 0,1
%A A096502 M. F. Hasler (www.univ-ag.fr/~mhasler), Apr 07 2008