A051896 a(n) = smallest palindrome > a(n-1) such that a(1)*a(2)*...*a(n) + 1 is prime with a(1) = 2.

2, 3, 5, 6, 9, 55, 66, 77, 88, 161, 191, 313, 484, 494, 525, 747, 3223, 3993, 11711, 13431, 13731, 18881, 19691, 21012, 21112, 22422, 24242, 34443, 35353, 41114, 44244, 44844, 46664, 52225, 52925, 53935, 58385, 59895, 60806, 64146, 71917

Offset: 1

Author

Felice Russo, Dec 21 1999

Keywords

• easy
• nice
• nonn
• base

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..200

Crossrefs

Cf. A046966, A051934, A051954.

Subsequence of A002113.

Programs

Mathematica

nxt[{t_,a_}]:=Module[{k=a+1},While[(!PalindromeQ[k])||CompositeQ[k*t+1],k++];{t*k,k}]; NestList[nxt,{2,2},40][[All,2]] (* Harvey P. Dale, Apr 18 2022 *)

Extensions

Initial conditions added to description by Chai Wah Wu, Apr 16 2021