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%I #13 Dec 24 2017 15:59:09
%S 0,1,2,3,4,5,6,7,8,9,10,12,21,23,32,34,43,45,54,56,65,67,76,78,87,89,
%T 98,131,135,202,242,246,313,353,357,420,424,464,468,531,535,575,579,
%U 642,646,686,753,757,797,864,868,975,979,1414,1474,2525,2585,3030,3036,3630,3636,3696,4141,4147,4741,4747,5252,5258,5852,5858,6303,6363,6369,6963,6969,7414,7474,8525,8585,9630,9636,9696,15151,15159,15951,15959,26262,37373,40404,40484,48404,48484,51515,51595,59515,59595,62626,73737,84040,84048,84840,84848,95151,95159,95951,95959,161616,272727,383838,494949,505050,616161,727272,838383,949494,1717171,2828282,3939393,6060606,7171717,8282828,9393939,18181818,29292929,70707070,81818181,92929292,191919191,808080808,919191919,9090909090
%N List of numbers k whose consecutive digits increase or decrease by d-1, where d is the number of digits in k.
%C Finite, 131 terms.
%t Range[0, 9]~Join~Select[Union[Range[10^5], Flatten@ Map[Map[FromDigits /@ {Drop[#, -1], #} &, Table[Flatten@ ConstantArray[#, k], {k, 3, 5}]] &, IntegerDigits@ Range[10, 99]]], If[Length@ #1 == 1, First@ #1 == #2 - 1, False] & @@ {Union@ Abs@ Differences@ #, Length@ #} &@ IntegerDigits[#] &] (* _Michael De Vlieger_, Dec 09 2017 *)
%o (PARI) is(n) = for(i=2, #n=digits(n), if(abs(n[i]-n[i-1]) != #n-1, return(0))); 1 \\ _Iain Fox_, Dec 08 2017
%K nonn,base,fini,full
%O 1,3
%A _Enrique Navarrete_, Dec 08 2017
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