%I #6 Apr 20 2023 17:50:05
%S 4,3,8,13,27,49,99,180,330,567,957,1546,2479,3865
%N The number of palindromic numbers which are the product of a number and its reversal with 2n-1 digits.
%C Every palindromic numbers which is the product of a number and its reversal has an odd number of digits.
%e a(1)=4 because there are 4 numbers matching the definition with one digit: 0*0=0; 1*1=1; 2*2=4; 3*3=9;
%e a(2)=3 because there are 3 numbers with three digits: 11*11=121; 12*21=252; 22*22=484;
%e a(3)=8 because there are 8 numbers with five digits: 101*101=10201; 111*111=12321; 121*121=14641; 102*201=20502; 112*211=23632; 122*221=26962; 202*202=40804; 212*212=44944;
%Y Cf. A158642.
%K nonn,base
%O 1,1
%A _Floris P. van Doorn_, Sep 25 2009