A084121 - OEIS

A084121

Primes p_n such that n*p_n is a palindrome.

2, 3, 11, 37, 53, 33827, 39119, 9260479, 10708871, 23858227, 65941772591

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OFFSET

1,1

COMMENTS

a(12) > 10^14. [Giovanni Resta, Jun 28 2013]

LINKS

Table of n, a(n) for n=1..11.

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

Cf. A084122, A084123.

Sequence in context: A038912 A019361 A093804 * A358867 A088747 A231574

Adjacent sequences: A084118 A084119 A084120 * A084122 A084123 A084124

KEYWORD

base,nonn

AUTHOR

Giovanni Resta, May 14 2003

STATUS

approved