Palindromes sandwiched between twin primes.

Terms

a(0) =4a(1) =6a(2) =282a(3) =828a(4) =858a(5) =2112a(6) =21012a(7) =21612a(8) =23832a(9) =26262a(10) =26862a(11) =28182a(12) =80208a(13) =81018a(14) =82728a(15) =84348a(16) =89598a(17) =89898a(18) =240042a(19) =246642a(20) =270072a(21) =276672a(22) =2035302a(23) =2109012a(24) =2136312a(25) =2155512a(26) =2182812a(27) =2422242a(28) =2428242a(29) =2460642