OFFSET
1,1
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
N:= 1000: # to get all entries <= 4*N+3
P:= select(isprime, [seq(4*i+3, i=0..N)]):
select(p -> convert(convert(p, base, 2), `+`)>=convert(convert(3*p, base, 2), `+`), P);
# Robert Israel, Jun 08 2014
PROG
(PARI) isok(p) = ((p%4) == 3) && (hammingweight(p) >= hammingweight(3*p)) && isprime(p); \\ Michel Marcus, Feb 13 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Irina Gerasimova, Mar 12 2014, a sockpuppet of Juri-Stepan Gerasimov.
STATUS
approved