login
Integers k such that A110299(k) is prime.
0

%I #15 Oct 03 2024 03:53:44

%S 1,2,3,5,10,17,21,28,38,50,86,88,100,375,408,630,646,1241,1860,4359,

%T 15444,17916,74901,91968,101121

%N Integers k such that A110299(k) is prime.

%C Integers k such that Sum_{i=0..k-1} 2^i*prime(k-i) is prime.

%e For these k, A110299(k) is 2, 7, 19, 101, 3727, 481577, 7706203, 986404613, ... all prime.

%o (PARI) isok(k) = isprime(fromdigits(primes(k), 2));

%Y Cf. A110299.

%K nonn,more

%O 1,2

%A _Michel Marcus_, Jan 04 2023

%E a(20)-a(22) from _Pontus von Brömssen_, Jan 04 2023

%E a(23)-a(25) from _Michael S. Branicky_, Oct 02 2024