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%I #7 Jan 24 2022 16:04:25
%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.
%H Robert Israel, <a href="/A164898/b164898.txt">Table of n, a(n) for n = 1..10000</a>
%p R[1]:= [1,3,5,7,9]:
%p for d from 2 to 3 do
%p R[d]:= map(t -> seq(10*t+i,i=[1,3,5,7,9]),R[d-1])
%p od:
%p B:= map(op,[seq(R[d],d=1..3)]):
%p B[2..-1]-B[1..-2]; # _Robert Israel_, Jan 24 2022
%t Differences[Select[Range[1000],Count[IntegerDigits[#],_?EvenQ]==0&]] (* _Harvey P. Dale_, Jan 03 2019 *)
%Y Cf. A014261.
%K nonn,base
%O 1,1
%A _Reinhard Zumkeller_, Aug 30 2009
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