OFFSET
1,1
COMMENTS
After a(194)=3977, there are no more terms < 100000.
Conjecture: a(194)=3977 is the final term.
For each of the first 194 terms k, there are at least as many primes in [1, k] as there are in [k+1, 2*k], and at least as many primes in [k+1, 2*k] as there are in [2*k+1, 3*k], so A342068(k)=4.
EXAMPLE
The intervals [1, 100], [101, 200], [201, 300], and [301, 400] contain 25, 21, 16, and 16 primes respectively (cf. A038822); the 4th interval does not contain more primes than does the 3rd, so 100 is not a term of the sequence.
However, the intervals [1, 101], [102, 202], [203, 303], and [304, 404] contain 26, 20, 16, and 17 primes, respectively; 17 > 16, so 101 is a term.
CROSSREFS
KEYWORD
nonn
AUTHOR
Jon E. Schoenfield, Mar 23 2021
STATUS
approved