login
A084121
Primes p_n such that n*p_n is a palindrome.
2
2, 3, 11, 37, 53, 33827, 39119, 9260479, 10708871, 23858227, 65941772591
OFFSET
1,1
COMMENTS
a(12) > 10^14. [Giovanni Resta, Jun 28 2013]
EXAMPLE
The 4119th prime 39119 is in the sequence since 4199*39119 = 161131161 is a palindrome.
MATHEMATICA
palQ[n_]:=FromDigits[Reverse[IntegerDigits[n]]]==n; t={}; Do[p=Prime[n]; If[palQ[p*n], AppendTo[t, p]], {n, 15*10^5}]; t (* Jayanta Basu, May 11 2013 *)
Module[{nn=2763*10^6}, Select[Thread[{Range[nn], Prime[Range[nn]]}], PalindromeQ[ Times@@ #]&]][[All, 2]] (* Requires Mathematica version 10 or later *) (* The program will take a long time to run. *) (* Harvey P. Dale, Jul 16 2020 *)
CROSSREFS
Sequence in context: A038912 A019361 A093804 * A358867 A088747 A231574
KEYWORD
base,nonn
AUTHOR
Giovanni Resta, May 14 2003
STATUS
approved