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A287217
Primes p where A196202 reaches a new local minimum, i.e., the value of A196202 is strictly smaller than the value for both the previous prime and the next prime.
0
7, 13, 19, 29, 37, 59, 71, 79, 89, 107, 131, 139, 151, 173, 191, 211, 233, 263, 277, 283, 313, 331, 359, 379, 389, 409, 439, 467, 491, 503, 521, 541, 569, 587, 599, 613, 647, 659, 677, 691, 739, 757, 773, 809, 823, 839, 857, 863, 881, 929, 941, 953, 977, 991
OFFSET
1,1
COMMENTS
A Wieferich prime p (A001220) is in this sequence iff neither A000040(i-1) nor A000040(i+1) is a Wieferich prime, where i is the index of p in A000040.
Conjecture: There are no consecutive Wieferich primes, i.e., A001220 is a subsequence of this sequence.
The truth of the previous conjecture would follow from the truth of the heuristic assumption that there are about log(log(x)) Wieferich primes below x for large x.
PROG
(PARI) a196202(n) = lift(Mod(2, n^2)^(n-1))
is(n) = (ispseudoprime(n)) && (a196202(n) < a196202(precprime(n-1))) && (a196202(n) < a196202(nextprime(n+1)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Felix Fröhlich, May 27 2017
STATUS
approved