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%I #25 May 22 2020 05:11:29
%S 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 18,895,36,109,14,59,32,63,58,18,2044,7,50,21,8,31,42,109,12,1022,106,
%U 19,112,97,4,35,36,35,1790,6,72,25,218,223,28,37,118,991,64
%N Regard the terms of A004290 as binary numbers and convert to base 10.
%C 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 a(n) < 2^n. - _Chai Wah Wu_, Apr 29 2015
%H Chai Wah Wu, <a href="/A257345/b257345.txt">Table of n, a(n) for n = 0..9998</a>
%t 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 (Python)
%o def A257345(n):
%o ....if n > 0:
%o ........for i in range(1,2**n):
%o ............x = int(format(i,'b'))
%o ............if not x % n:
%o ................return int(str(x),2)
%o ....return 0 # _Chai Wah Wu_, Apr 29 2015
%Y Cf. A079339, A004290, A131577.
%K nonn,base
%O 0,3
%A _N. J. A. Sloane_, Apr 29 2015
%E More terms from _Chai Wah Wu_, Apr 29 2015
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