A071278 - OEIS

%I #15 Jul 08 2024 02:28:38

%S 6,8,10,12,12,14,15,16,18,18,20,21,22,24,24,27,28,30,32,33,35,36,40,

%T 42,44,44,45,48,54,55,56,63,66,66,66,72,77,88,88,88,99,99,110,110,132,

%U 132,132,132,154,154,165,165,176,176,176,198,198,198,198,202,220,220,222

%N Sorted list of numbers b(i)*b(j), 2 < i < j, where b = A002113 = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 33 ... is a list of the decimal palindromes.

%C Old name was: Palindromes which are nontrivial multiples of 2 distinct palindromes.

%C Repetitions are allowed. 12 appears twice because it is both 2*6 and 3*4.

%e 8 is in the sequence because 8=2*4.

%t Module[{nn=250,pals},pals=Select[Range[2,nn],PalindromeQ];Select[Sort[ Times@@#&/@ Subsets[pals,{2}]],#<=nn&]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, May 27 2018 *)

%Y Cf. A002113.

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Jun 07 2002

%E Corrected and extended by _Sascha Kurz_, Jan 02 2003

%E Edited (with corrected definition) by _N. J. A. Sloane_, May 27 2018