Exactly 3 out of 10m+1, 10m+3, 10m+7, 10m+9 are primes.

Terms

a(0) =4a(1) =7a(2) =13a(3) =22a(4) =31a(5) =43a(6) =46a(7) =61a(8) =64a(9) =85a(10) =88a(11) =103a(12) =106a(13) =109a(14) =130a(15) =142a(16) =145a(17) =160a(18) =166a(19) =169a(20) =178a(21) =199a(22) =238a(23) =268a(24) =271a(25) =316a(26) =367a(27) =376a(28) =391a(29) =400