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A257345 Regard the terms of A004290 as binary numbers and convert to base 10.

%I A257345 #31 Sep 20 2024 23:53:57
%S A257345 0,1,2,7,4,2,14,9,8,511,2,3,28,9,18,14,16,29,1022,25,4,21,6,53,56,4,
%T A257345 18,895,36,109,14,59,32,63,58,18,2044,7,50,21,8,31,42,109,12,1022,106,
%U A257345 19,112,97,4,35,36,35,1790,6,72,25,218,223,28,37,118,991,64
%N A257345 Regard the terms of A004290 as binary numbers and convert to base 10.
%C A257345 Of course the terms of A004290 are already in base 10 (they just happen to involve only the digits 0 and 1), so there is no justification for this sequence other than curiosity.
%C A257345 a(n) < 2^n. - _Chai Wah Wu_, Apr 29 2015
%H A257345 Chai Wah Wu, <a href="/A257345/b257345.txt">Table of n, a(n) for n = 0..9998</a>
%t A257345 s = With[{c = Rest[Union[FromDigits /@ Flatten[Table[Tuples[{1, 0}, i], {i, 10}], 1]]]}, Join[{0}, Flatten[Table[Select[c, Divisible[#, n] &, 1], {n, 120}]]]]; FromDigits[IntegerDigits@ #, 2] & /@ s (* _Michael De Vlieger_, Apr 29 2015, after _Harvey P. Dale_ at A004290 *)
%o A257345 (Python)
%o A257345 def A257345(n):
%o A257345     if n > 0:
%o A257345         for i in range(1, 2**n):
%o A257345             x = int(format(i, 'b'))
%o A257345             if not x % n:
%o A257345                 return int(str(x), 2)
%o A257345     return 0 # _Chai Wah Wu_, Apr 29 2015
%Y A257345 Cf. A079339, A004290, A131577.
%K A257345 nonn,base
%O A257345 0,3
%A A257345 _N. J. A. Sloane_, Apr 29 2015
%E A257345 More terms from _Chai Wah Wu_, Apr 29 2015