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A073547 Numbers k such that antid(k) = antid(k+1), where antid(k) = A066272(k).

%I A073547 #19 Apr 13 2024 14:55:18
%S A073547 1,3,8,10,14,19,20,22,27,29,40,42,46,49,52,58,65,70,74,75,82,87,90,91,
%T A073547 94,102,103,112,116,118,122,124,131,135,148,149,151,154,157,159,171,
%U A073547 180,183,187,188,198,204,205,208,212,213,214,217,220,222,227,231,232
%N A073547 Numbers k such that antid(k) = antid(k+1), where antid(k) = A066272(k).
%H A073547 Robert Israel, <a href="/A073547/b073547.txt">Table of n, a(n) for n = 1..10000</a>
%p A073547 N:= 1000: # to get all terms <= N-1
%p A073547 V:= Vector(N):
%p A073547 for k from 1 to floor(N/3) do
%p A073547   R1:= [seq(i, i=3*k .. N, 2*k)];
%p A073547   V[R1]:= map(`+`,V[R1],1);
%p A073547   R2:= [seq(i, i=3*k+1 .. N, 2*k+1)];
%p A073547   V[R2]:= map(`+`,V[R2],1);
%p A073547   R3:= [seq(i,i=3*k+2 .. N, 2*k+1)];
%p A073547   V[R3]:= map(`+`,V[R3],1);
%p A073547 od:
%p A073547 select(t -> V[t]=V[t+1], [$1..N-1]); # _Robert Israel_, Sep 26 2016
%t A073547 at[n_] := Count[Flatten[Quotient[#, Rest[Select[Divisors[#], OddQ]]] & /@ (2 n + Range[-1, 1])], Except[1]]; Select[Range[232], at[#] == at[# + 1] &] (* _Jayanta Basu_, Jul 01 2013 *)
%Y A073547 Cf. A066272.
%K A073547 easy,nonn
%O A073547 1,2
%A A073547 _Jason Earls_, Aug 31 2002