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A088001 a(n) is the sum of non-palindromic divisors of n.

%I A088001 #28 May 15 2025 18:51:48
%S A088001 0,0,0,0,0,0,0,0,0,10,0,12,13,14,15,16,17,18,19,30,21,0,23,36,25,39,
%T A088001 27,42,29,55,31,48,0,51,35,66,37,57,52,70,41,77,43,0,60,69,47,100,49,
%U A088001 85,68,91,53,99,0,98,76,87,59,147,61,93,84,112,78,0,67,119,92,129,71,162,73
%N A088001 a(n) is the sum of non-palindromic divisors of n.
%H A088001 Indranil Ghosh, <a href="/A088001/b088001.txt">Table of n, a(n) for n = 1..10000</a>
%F A088001 a(n)=0 iff all divisors are palindromic. See A062687.
%F A088001 a(n)+A088000(n) = A000203(n). - _R. J. Mathar_, Sep 09 2015
%p A088001 A088001 := proc(n)
%p A088001         numtheory[sigma](n)-A088000(n) ;
%p A088001 end proc; # _R. J. Mathar_, Jul 28 2016
%t A088001 Table[Plus @@ Select[Divisors[k], Reverse[x = IntegerDigits[#]] != x &], {k, 73}] (* _Jayanta Basu_, Aug 12 2013 *)
%t A088001 Table[Total[Select[Divisors[n],!PalindromeQ[#]&]],{n,80}] (* _Harvey P. Dale_, May 15 2025 *)
%o A088001 (Python)
%o A088001 def ispal(n):
%o A088001     return n==int(str(n)[::-1])
%o A088001 def A088001(n):
%o A088001     s=0
%o A088001     for i in range(1, n+1):
%o A088001         if n%i==0 and not ispal(i):
%o A088001              s+=i
%o A088001     return s # _Indranil Ghosh_, Feb 10 2017
%Y A088001 Cf. A087999, A088000, A088002.
%K A088001 base,nonn
%O A088001 1,10
%A A088001 _Labos Elemer_, Oct 14 2003