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A032945 Numbers k whose base-10 representation Sum_{i=0..m} d(i)*10^(m-i) has d(i)=0 for all odd i. Here m is the position of the lead digit of k.

%I A032945 #27 Apr 12 2022 22:29:23
%S A032945 0,1,2,3,4,5,6,7,8,9,10,20,30,40,50,60,70,80,90,100,101,102,103,104,
%T A032945 105,106,107,108,109,200,201,202,203,204,205,206,207,208,209,300,301,
%U A032945 302,303,304,305,306,307,308,309,400,401,402,403
%N A032945 Numbers k whose base-10 representation Sum_{i=0..m} d(i)*10^(m-i) has d(i)=0 for all odd i. Here m is the position of the lead digit of k.
%C A032945 Every nonnegative integer can be represented as the sum of two members of this sequence. - _Franklin T. Adams-Watters_, Aug 30 2014
%C A032945 This first differs from A236402 at a(110)=1000 (followed by 1010, 1020, 1030, ...), while A236402(110)=910 (followed by 1000, 1001, 1002, ...). - _M. F. Hasler_, Dec 28 2014
%H A032945 Robert Israel, <a href="/A032945/b032945.txt">Table of n, a(n) for n = 1..10000</a>
%p A032945 N:= 6: # to get all terms with up to N digits
%p A032945 A[1]:= 0:
%p A032945 count:= 1:
%p A032945 for d from 1 to N do
%p A032945    dp:= ceil(d/2);
%p A032945    for j from 10^(dp-1) to 10^dp-1 do
%p A032945       L:= ListTools[Reverse](convert(j,base,10));
%p A032945       L:= ListTools[Interleave](L,[0$(d-dp)]);
%p A032945       count:= count+1;
%p A032945       A[count]:= add(L[i]*10^(d-i),i=1..d);
%p A032945     od
%p A032945 od:
%p A032945 seq(A[i],i=1..count); # _Robert Israel_, Aug 31 2014
%o A032945 (PARI) is(n)=!forstep(i=2,#n=digits(n),2,n[i]&&return) \\ _M. F. Hasler_, Dec 28 2014
%o A032945 (Python)
%o A032945 def ok(n): return str(n)[1::2].strip('0') == ""
%o A032945 print([k for k in range(404) if ok(k)]) # _Michael S. Branicky_, Apr 12 2022
%Y A032945 Cf. A126684.
%K A032945 nonn,base
%O A032945 1,3
%A A032945 _Clark Kimberling_
%E A032945 Definition corrected by _Franklin T. Adams-Watters_, Aug 30 2014