OFFSET
1,1
COMMENTS
Dinculescu observes that when k^2 > 1 is a twin rank (i.e., in A002822) then 5 | k (k is divisible by 5), and if k^3 is a twin rank, then 7 | k; cf. A326232 & A326234. It is unknown whether there are other pairs (a, b) such that a | n whenever n^b > 1 is a twin rank. (Of course 2 | b => 5 | a and 3 | b => 7 | a, so we aren't interested in pairs (a, b) which are consequence of this.)
LINKS
A. Dinculescu, On the Numbers that Determine the Distribution of Twin Primes, Surveys in Mathematics and its Applications, 13 (2018), 171-181.
PROG
(PARI) a(n)=for(k=2, oo, ispseudoprime(6*k^n-1)&&ispseudoprime(6*k^n+1)&&return(k))
CROSSREFS
KEYWORD
nonn
AUTHOR
M. F. Hasler and Antonie Dinculescu, Jun 16 2019
STATUS
approved