proposed
approved
editing
Cf. A000040, A057735, A058958 (associated k).
Michel Marcus: also in 2nd part of xrefs
a = Delete[Union[Flatten[Table[If [PrimeQ[3^n + 4] == True, 3^ n + 4, 0], {n, 1, 200}]]], 1]
Cf. primesPrimes of the form 3^k + d: A057735 (d=2), this sequence (d=4), A102870 (d=8), A102907 (d=10), A102874 (d=14), A243437 (d=16), A102904 (d=20), A243438 (d=22), A243439 (d=26), A102906 (d=28).
Cf. primes of the form 3^n + k + d: A057735 (kd=2), this sequence (kd=4), A102870 (kd=8), A102907 (kd=10), A102874 (kd=14), A243437 (kd=16), A102904 (kd=20), A243438 (kd=22), A243439 (kd=26), A102906 (kd=28).
Cf. A000040, A057735., A058958 (associated k).
Cf. A058958 (associated k).