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%I #18 Nov 14 2019 15:45:26
%S 101,110,111,112,113,114,115,116,117,118,119,121,123,131,135,141,147,
%T 151,159,161,171,181,191,202,210,212,220,221,222,223,224,225,226,227,
%U 228,229,232,234,242,246,252,258,262,272,282,292,303,313,321,323,330,331
%N Numbers with at least three digits such that the absolute differences between successive digits forms a palindrome (when leading zeros are omitted).
%C All numbers from 0 to 99 trivially have the property, so we require at least three digits.
%C Question: There seems to be a pattern. Can someone find a formula for index of a given member?
%H Harvey P. Dale, <a href="/A086918/b086918.txt">Table of n, a(n) for n = 1..1000</a>
%e 112 is a member yielding (0)2.
%e 131 and 135 both are members and the palindrome arising in both cases is 22.
%t Select[Range[100,500],PalindromeQ[FromDigits[Abs[ Differences[ IntegerDigits[ #]]]]]&] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Nov 14 2019 *)
%Y Cf. A086919.
%K base,easy,nonn
%O 1,1
%A _Amarnath Murthy_, Sep 18 2003
%E Corrected and extended by _Harvey P. Dale_, Nov 14 2019
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