Economical palindromes.

Terms

a(0) =343a(1) =1331a(2) =10201a(3) =14641a(4) =31213a(5) =94249a(6) =1030301a(7) =1332331a(8) =1367631a(9) =1478741a(10) =2060602a(11) =2513152a(12) =2551552a(13) =2570752a(14) =2939392a(15) =2977792a(16) =3090903a(17) =3498943a(18) =3637363a(19) =3735373a(20) =3850583a(21) =5221225a(22) =5265625a(23) =5734375a(24) =6948496a(25) =11288211a(26) =11333311a(27) =12100121a(28) =12499421a(29) =13577531