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A164898 First differences of numbers having only odd digits in their decimal representation. 2

%I

%S 2,2,2,2,2,2,2,2,2,12,2,2,2,2,12,2,2,2,2,12,2,2,2,2,12,2,2,2,2,12,2,2,

%T 2,2,12,2,2,2,2,12,2,2,2,2,12,2,2,2,2,12,2,2,2,2,112,2,2,2,2,12,2,2,2,

%U 2,12,2,2,2,2,12,2,2,2,2,12,2,2,2,2,112,2,2,2,2,12,2,2,2,2,12,2,2,2,2,12

%N First differences of numbers having only odd digits in their decimal representation.

%C a(n) = A014261(n+1) - A014261(n);

%C all terms are of the form (10^k + 8)/9, see A047855;

%C a(n) > 2 iff A014261(n) mod 10 = 9.

%t Differences[Select[Range[1000],Count[IntegerDigits[#],_?EvenQ]==0&]] (* _Harvey P. Dale_, Jan 03 2019 *)

%K nonn,base

%O 1,1

%A _Reinhard Zumkeller_, Aug 30 2009

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Last modified May 17 21:11 EDT 2021. Contains 343990 sequences. (Running on oeis4.)