OFFSET
1,1
LINKS
FUNG Cheok Yin, Table of n, a(n) for n = 1..10000
Mohamed El Bachraoui, Primes in the interval [2n, 3n] (2006)
FUNG Cheok Yin, C++ program
FORMULA
PROG
(PARI) A289493(n)=primepi(3*n)-if(n>1, primepi(2*n)) \\ M. F. Hasler, Sep 29 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
FUNG Cheok Yin, Jul 07 2017
STATUS
approved