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A031235 Triangle T(n,k): write n in base 5, reverse order of digits.

%I A031235 #27 Apr 17 2020 07:20:15
%S A031235 0,1,2,3,4,0,1,1,1,2,1,3,1,4,1,0,2,1,2,2,2,3,2,4,2,0,3,1,3,2,3,3,3,4,
%T A031235 3,0,4,1,4,2,4,3,4,4,4,0,0,1,1,0,1,2,0,1,3,0,1,4,0,1,0,1,1,1,1,1,2,1,
%U A031235 1,3,1,1,4,1,1,0,2,1,1,2,1,2,2,1,3,2,1,4,2,1,0
%N A031235 Triangle T(n,k): write n in base 5, reverse order of digits.
%H A031235 Reinhard Zumkeller, <a href="/A031235/b031235.txt">Rows n = 0..1000 of triangle, flattened</a>
%t A031235 Reverse[IntegerDigits[#,5]]&/@Range[0,40]//Flatten (* _Harvey P. Dale_, Aug 02 2016 *)
%o A031235 (PARI) A031235(n, k=-1)=/*k<0&&error("Flattened sequence not yet implemented.")*/n\5^k%5 \\ Assuming that columns are numbered starting with k=0 as in A030308, A030341, ... - _M. F. Hasler_, Jul 21 2013
%o A031235 (Haskell)
%o A031235 a031235 n k = a031235_tabf !! n !! k
%o A031235 a031235_row n = a031235_tabf !! n
%o A031235 a031235_tabf = iterate succ [0] where
%o A031235    succ []     = [1]
%o A031235    succ (4:ts) = 0 : succ ts
%o A031235    succ (t:ts) = (t + 1) : ts
%o A031235 -- _Reinhard Zumkeller_, Sep 18 2015
%Y A031235 Cf. A030308, A030341, A030386, A030567, A031007, A031045, A031087, A031298 for the base-2 to base-10 analogs.
%Y A031235 Cf. A007091.
%K A031235 nonn,base,tabf,less
%O A031235 0,3
%A A031235 _Clark Kimberling_
%E A031235 Initial 0 and better name by _Philippe Deléham_, Oct 20 2011