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%I M4814 #34 Mar 12 2021 01:51:51
%S 3,11,1011,1111110011,1000010001110100011000101111011
%N Convert the last term from decimal to binary!
%C The next term (a(5)) has 100 digits. - _Harvey P. Dale_, Feb 28 2012
%C The number of digits of a(n) are 2, 4, 10, 31, 100, 330, 1093, 3628, 12049, 40023, 132951, 441651, 1467130, 4873698, 16190071, 53782249, 178660761, ... - _Robert G. Wilson v_, Jul 10 2013
%C log(a(n))/log(a(n-1)) = ~log_2(10) = A020862. - _Robert G. Wilson v_, Jul 10 2013
%D C. Pickover, Mazes for the Mind, St. Martin's Press, NY, 1992, p. 350.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%t NestList[FromDigits[IntegerDigits[#,2]]&,11,4] (* _Harvey P. Dale_, Feb 28 2012 *)
%o (Python)
%o def agen(an):
%o while True: yield an; an = int(bin(an)[2:])
%o g = agen(3)
%o print([next(g) for i in range(5)]) # _Michael S. Branicky_, Mar 11 2021
%Y For initial terms 2 through 12 see A008559, A006938, A260025, A260024, A260026, A260027, A260028, A260029, A008559 (again), A006938 (again), A260030 respectively.
%K nonn,base
%O 1,1
%A _N. J. A. Sloane_
%E a(1)=3 added by _N. J. A. Sloane_, Jul 14 2015