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A068109 a(1) = 0, a(2) = 1, a(n) = concatenate(a(n-1) and a(n-2)) - a(n-1).

%I A068109 #20 Apr 28 2023 11:22:19
%S A068109 0,1,9,82,747,74035,73961712,7396097312323,739609723836276649389,
%T A068109 7396097238362026884173559820662934,
%U A068109 7396097238362026884166163723424572712725550276455986455
%N A068109 a(1) = 0, a(2) = 1, a(n) = concatenate(a(n-1) and a(n-2)) - a(n-1).
%H A068109 Stefano Spezia, <a href="/A068109/b068109.txt">Table of n, a(n) for n = 1..17</a>
%e A068109 a(5) = 82|9 - 82 = 747.
%p A068109 a:= proc(n) option remember; `if`(n<3, n-1, (l->
%p A068109       add(l[i]*10^(i-1), i=1..nops(l))-a(n-1))(map(
%p A068109       x-> convert(x, base, 10)[], [a(n-2),a(n-1)])))
%p A068109     end:
%p A068109 seq(a(n), n=1..12);  # _Alois P. Heinz_, Jun 09 2021
%t A068109 a[1]=0; a[2]=1; a[n_]:=FromDigits[Join[IntegerDigits[a[n-1]],IntegerDigits[a[n-2]]]]-a[n-1]; Array[a,12] (* _Stefano Spezia_, Apr 25 2023 *)
%o A068109 (Python)
%o A068109 def f(v): return int((str(v[-1])+str(v[-2]))) - v[-1]
%o A068109 def aupton(nn):
%o A068109     alst = [0, 1]
%o A068109     for n in range(2, nn+1): alst.append(f(alst))
%o A068109     return alst[:nn+1]
%o A068109 print(aupton(10)) # _Michael S. Branicky_, Jun 09 2021
%K A068109 nonn,base,easy
%O A068109 1,3
%A A068109 _Benoit Cloitre_, Mar 21 2002