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

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, 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, 1, 3, 1, 1, 4, 1, 1, 0, 2, 1, 1, 2, 1, 2, 2, 1, 3, 2, 1, 4, 2, 1, 0

Offset

0,3

Links

Reinhard Zumkeller, Rows n = 0..1000 of triangle, flattened

Mathematica

Reverse[IntegerDigits[#, 5]]&/@Range[0, 40]//Flatten (* Harvey P. Dale, Aug 02 2016 *)

Prog

(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
(Haskell)
a031235 n k = a031235_tabf !! n !! k
a031235_row n = a031235_tabf !! n
a031235_tabf = iterate succ [0] where
   succ []     = [1]
   succ (4:ts) = 0 : succ ts
   succ (t:ts) = (t + 1) : ts
-- Reinhard Zumkeller, Sep 18 2015

Crossrefs

Cf. A030308, A030341, A030386, A030567, A031007, A031045, A031087, A031298 for the base-2 to base-10 analogs.

Cf. A007091.

Sequence in context: A023868 A122275 A197024 * A090141 A378366 A049264

Adjacent sequences: A031232 A031233 A031234 * A031236 A031237 A031238

Keyword

nonn,base,tabf,less

Author

Clark Kimberling

Extensions

Initial 0 and better name by Philippe Deléham, Oct 20 2011

Status

approved