Primes p such that 1p1, 3p3, 7p7 and 9p9 are all primes.

Terms

a(0) =53a(1) =2477a(2) =4547a(3) =5009a(4) =7499a(5) =8831a(6) =9839a(7) =11027a(8) =24821a(9) =26393a(10) =29921a(11) =36833a(12) =46073a(13) =46769a(14) =47711a(15) =49307a(16) =53069a(17) =59621a(18) =64283a(19) =66041a(20) =79901a(21) =84017a(22) =93263a(23) =115679a(24) =133103a(25) =151121a(26) =169523a(27) =197651a(28) =207017a(29) =236807