Numbers k such that 2*prime(k+2) + product (first k odd primes) is prime, i.e., k such that primorial(k+1)/2 + 2*prime(k+2) is prime.

A139461

Numbers k such that 2*prime(k+2) + product (first k odd primes) is prime, i.e., k such that primorial(k+1)/2 + 2*prime(k+2) is prime.

Terms

    a(0) =1a(1) =2a(2) =3a(3) =4a(4) =8a(5) =9a(6) =11a(7) =12a(8) =27a(9) =28a(10) =37a(11) =47a(12) =64a(13) =321a(14) =415a(15) =1222a(16) =1649a(17) =2937a(18) =3600a(19) =6149a(20) =12481

External references