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A030373 Write n in base 4 and juxtapose.

%I A030373 #50 Jul 22 2025 16:52:38
%S A030373 1,2,3,1,0,1,1,1,2,1,3,2,0,2,1,2,2,2,3,3,0,3,1,3,2,3,3,1,0,0,1,0,1,1,
%T A030373 0,2,1,0,3,1,1,0,1,1,1,1,1,2,1,1,3,1,2,0,1,2,1,1,2,2,1,2,3,1,3,0,1,3,
%U A030373 1,1,3,2,1,3,3,2,0,0,2,0,1,2,0,2,2,0,3,2,1,0
%N A030373 Write n in base 4 and juxtapose.
%C A030373 An irregular table in which the n-th row lists the base-4 digits of n. - _Jason Kimberley_, Nov 26 2012
%C A030373 The base-4 Champernowne constant: it is normal in base 4. - _Jason Kimberley_, Nov 26 2012
%H A030373 R. J. Mathar, <a href="/A030373/b030373.txt">Table of n, a(n) for n = 1..4664</a>
%H A030373 F. J. Aragon Artacho, D. H. Bailey, J. M. Borwein, and P. B. Borwein, <a href="https://carma.newcastle.edu.au/walks/publications.html">Walking on real numbers</a>, preprint September 2012.
%e A030373 1;
%e A030373 2;
%e A030373 3;
%e A030373 1,0;
%e A030373 1,1;
%e A030373 1,2;
%e A030373 1,3;
%e A030373 2,0;
%e A030373 2,1;
%e A030373 2,2;
%e A030373 ...
%e A030373 3,3;
%e A030373 1,0,0;
%e A030373 1,0,1;
%e A030373 1,0,2;
%e A030373 1,0,3;
%e A030373 1,1,0; ....
%t A030373 Flatten[IntegerDigits[Range[40],4]] (* _Harvey P. Dale_, Aug 23 2011 *)
%o A030373 (Magma) &cat[Reverse(IntegerToSequence(n,4)):n in[1..31]]; // _Jason Kimberley_, Dec 07 2012
%o A030373 (Python)
%o A030373 from itertools import count, chain, islice
%o A030373 from sympy.ntheory.factor_ import digits
%o A030373 def A030373_gen(): return chain.from_iterable(digits(m, 4)[1:] for m in count(1))
%o A030373 A030373_list = list(islice(A030373_gen(), 30)) # _Chai Wah Wu_, Jan 07 2022
%Y A030373 Cf. A007376, A003137, A007090.
%Y A030373 Tables in which the n-th row lists the base b digits of n: A030190 and A030302 (b=2), A003137 and A054635 (b=3), this sequence (b=4), A031219 (b=5), A030548 (b=6), A030998 (b=7), A031035 and A054634 (b=8), A031076 (b=9), A007376 and A033307 (b=10). - _Jason Kimberley_, Dec 06 2012
%K A030373 nonn,base,cons,tabf,easy
%O A030373 1,2
%A A030373 _Clark Kimberling_