cp's OEIS Frontend

A383061 Positive integers that contain an odd digit d immediately preceded by a digit >= d.

%I A383061 #12 Apr 30 2025 11:08:46
%S A383061 11,21,31,33,41,43,51,53,55,61,63,65,71,73,75,77,81,83,85,87,91,93,95,
%T A383061 97,99,110,111,112,113,114,115,116,117,118,119,121,131,133,141,143,
%U A383061 151,153,155,161,163,165,171,173,175,177,181,183,185,187,191,193,195,197,199
%N A383061 Positive integers that contain an odd digit d immediately preceded by a digit >= d.
%C A383061 Conjecture: these are the numbers missing from A383059.
%H A383061 Paolo Xausa, <a href="/A383061/b383061.txt">Table of n, a(n) for n = 1..10000</a>
%t A383061 A383061Q[k_] := MemberQ[Partition[IntegerDigits[k], 2, 1], {i_, j_?OddQ} /; i >= j];
%t A383061 Select[Range[200], A383061Q]
%o A383061 (Python)
%o A383061 def ok(n):
%o A383061     s = str(n)
%o A383061     return any(s[i] <= s[i-1] for i in range(1, len(s)) if s[i] in "13579")
%o A383061 print([k for k in range(200) if ok(k)]) # _Michael S. Branicky_, Apr 19 2025
%Y A383061 Cf. A383059, A383062 (complement).
%Y A383061 Cf. A347298, A382464, A382623, A382937, A383245, A383247, A383249, A383500.
%K A383061 nonn,base,easy
%O A383061 1,1
%A A383061 _Paolo Xausa_, Apr 18 2025