A340252 Numbers whose pairwise products of divisors are all palindromic.

1, 2, 3, 4, 5, 7, 11, 22, 33, 101, 121, 131, 151, 181, 191, 202, 303, 313, 353, 373, 383, 727, 757, 787, 797, 919, 929, 1111, 2222, 10201, 10301, 10501, 10601, 11311, 11411, 12221, 12421, 12721, 12821, 13331, 13831, 13931, 14341, 14741, 15451, 15551, 16061, 16361, 16561, 16661

Offset: 1

Author

Ivan N. Ianakiev, Jan 02 2021

Keywords

• base
• easy
• nonn

Comments

Supersequence of A002385 (palindromic primes).

A subsequence of A062687 (numbers all of whose divisors are palindromic).

Examples

			The pairwise products of the divisors of 22 (2,11,22,44,242) are all palindromic, so 22 is in the sequence.
		

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A002385, A062687.

Programs

Mathematica

fQ[n_]:=AllTrue[Union[Times@@@Subsets[Divisors[n],{2}]],PalindromeQ]; Select[Range[20000],fQ]