OFFSET
1,1
COMMENTS
Numbers k of the form 2^a*3^b such that k+1 and (k+2)/2 are prime.
All terms except 2 and 4 are in A325204.
All terms except 4 end in 2 or 6.
LINKS
Ray Chandler, Table of n, a(n) for n = 1..41 (terms < 10^1000; first 39 terms from Robert Israel)
EXAMPLE
a(3)=12 is a term because 12=2^2*3 and 13 and 14/2 are prime.
MAPLE
N:= 10^100: # to get terms <= N
sort(select(t -> isprime(t+1) and isprime((t+2)/2), [seq(seq(2^i*3^j, i = 1 .. ilog2(N/3^j)), j=0..floor(log[3](N)))]));
CROSSREFS
KEYWORD
nonn
AUTHOR
Robert Israel, Sep 05 2019
STATUS
approved