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A184392 a(n) is the product of palindromic divisors of n.

%I A184392 #31 May 01 2021 15:57:31
%S A184392 1,2,3,8,5,36,7,64,27,10,11,144,1,14,15,64,1,324,1,40,21,484,1,1152,5,
%T A184392 2,27,56,1,180,1,64,1089,2,35,1296,1,2,3,320,1,252,1,85184,135,2,1,
%U A184392 1152,7,10,3,8,1,324,3025,448,3,2,1,720,1,2,189,64,5,18974736,1,8,3,70,1,10368,1,2,15,8,5929,36,1,320,27,2,1,1008,5,2,3,59969536,1,1620,7,8,3,2,5,1152,1,14,970299,40
%N A184392 a(n) is the product of palindromic divisors of n.
%H A184392 Indranil Ghosh, <a href="/A184392/b184392.txt">Table of n, a(n) for n = 1..10000</a>
%F A184392 a(n) = A007955(n) / A179937(n).
%e A184392 For n = 20, set of palindromic divisors is {1, 2, 4, 5}; a(12) = 1*2*4*5 = 40.
%t A184392 palQ[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]]; f[n_]:=Times@@Select[Divisors[n],palQ]; Table[f[n],{n,100}]  (* _Harvey P. Dale_, Jan 21 2011 *)
%o A184392 (Python)
%o A184392 def ispal(n):
%o A184392     return n==int(str(n)[::-1])
%o A184392 def A184392(n):
%o A184392     s=1
%o A184392     for i in range(1, n+1):
%o A184392         if n%i==0 and ispal(i):
%o A184392              s*=i
%o A184392     return s # _Indranil Ghosh_, Feb 10 2017
%Y A184392 Cf. A007955, A087990, A087991, A088000, A088001, A179937.
%K A184392 nonn,base
%O A184392 1,2
%A A184392 _Jaroslav Krizek_, Jan 12 2011
%E A184392 More terms from _Harvey P. Dale_, Jan 21 2011