

A086918


Numbers with at least three digits such that the absolute differences between successive digits forms a palindrome (when leading zeros are omitted).


3



101, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 123, 131, 135, 141, 147, 151, 159, 161, 171, 181, 191, 202, 210, 212, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 232, 234, 242, 246, 252, 258, 262, 272, 282, 292, 303, 313, 321, 323, 330, 331
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OFFSET

1,1


COMMENTS

All numbers from 0 to 99 trivially have the property, so we require at least three digits.
Question: There seems to be a pattern. Can someone find a formula for index of a given member?


LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000


EXAMPLE

112 is a member yielding (0)2.
131 and 135 both are members and the palindrome arising in both cases is 22.


MATHEMATICA

Select[Range[100, 500], PalindromeQ[FromDigits[Abs[ Differences[ IntegerDigits[ #]]]]]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Nov 14 2019 *)


CROSSREFS

Cf. A086919.
Sequence in context: A092628 A107219 A140799 * A259300 A025349 A025341
Adjacent sequences: A086915 A086916 A086917 * A086919 A086920 A086921


KEYWORD

base,easy,nonn


AUTHOR

Amarnath Murthy, Sep 18 2003


EXTENSIONS

Corrected and extended by Harvey P. Dale, Nov 14 2019


STATUS

approved



