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A088000 a(n) is the sum of the palindromic divisors of n.

%I A088000 #29 May 01 2021 08:03:19
%S A088000 1,3,4,7,6,12,8,15,13,8,12,16,1,10,9,15,1,21,1,12,11,36,1,24,6,3,13,
%T A088000 14,1,17,1,15,48,3,13,25,1,3,4,20,1,19,1,84,18,3,1,24,8,8,4,7,1,21,72,
%U A088000 22,4,3,1,21,1,3,20,15,6,144,1,7,4,15,1,33,1,3,9,7,96,12,1,20,13,3,1,23,6,3
%N A088000 a(n) is the sum of the palindromic divisors of n.
%H A088000 Indranil Ghosh, <a href="/A088000/b088000.txt">Table of n, a(n) for n = 1..10000</a>
%e A088000 n=14: a(14)=1+2+7=10;
%e A088000 n=101: a(101)=1+101=102;
%p A088000 A088000 := proc(n)
%p A088000     a := 0 ;
%p A088000     for d in numtheory[divisors](n) do
%p A088000         if isA002113(d) then
%p A088000             a := a+d ;
%p A088000         end if;
%p A088000     end do;
%p A088000     a ;
%p A088000 end proc:
%p A088000 seq(A088000(n),n=1..100) ; # _R. J. Mathar_, Sep 09 2015
%t A088000 Table[Plus @@ Select[Divisors[k], Reverse[x = IntegerDigits[#]] == x &], {k, 86}] (* _Jayanta Basu_, Aug 12 2013 *)
%o A088000 (Python)
%o A088000 def ispal(n):
%o A088000     return n==int(str(n)[::-1])
%o A088000 def A088000(n):
%o A088000     s=0
%o A088000     for i in range(1, n+1):
%o A088000         if n%i==0 and ispal(i):
%o A088000              s+=i
%o A088000     return s
%o A088000 print([A088000(n) for n in range(1,30)]) # _Indranil Ghosh_, Feb 10 2017
%o A088000 (PARI) a(n) = sumdiv(n, d, my(dd=digits(d)); if (Vecrev(dd) == dd, d)); \\ _Michel Marcus_, Apr 06 2020
%Y A088000 Cf. A062687 (all divisors are palindromic), A087990 (number of palindromic divisors).
%K A088000 base,nonn
%O A088000 1,2
%A A088000 _Labos Elemer_, Oct 14 2003