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A031076
Write n in base 9 and juxtapose.
33
1, 2, 3, 4, 5, 6, 7, 8, 1, 0, 1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 2, 0, 2, 1, 2, 2, 2, 3, 2, 4, 2, 5, 2, 6, 2, 7, 2, 8, 3, 0, 3, 1, 3, 2, 3, 3, 3, 4, 3, 5, 3, 6, 3, 7, 3, 8, 4, 0, 4, 1, 4, 2, 4, 3, 4, 4, 4, 5, 4, 6, 4, 7, 4, 8, 5, 0, 5, 1, 5, 2, 5, 3, 5, 4
OFFSET
1,2
COMMENTS
An irregular table in which the n-th row lists the base-9 digits of n. - Jason Kimberley, Dec 07 2012
The base-9 Champernowne constant: it is normal in base 9. - Jason Kimberley, Dec 07 2012
LINKS
MATHEMATICA
Flatten@ IntegerDigits[ Range@ 55, 9] (* or *)
almostNatural[n_, b_] := Block[{m = 0, d = n, i = 1, l, p}, While[m <= d, l = m; m = (b - 1) i*b^(i - 1) + l; i++]; i--; p = Mod[d - l, i]; q = Floor[(d - l)/i] + b^(i - 1); If[p != 0, IntegerDigits[q, b][[p]], Mod[q - 1, b]]]; Array[ almostNatural[#, 9] &, 105] (* Robert G. Wilson v, Jul 01 2014 *)
PROG
(Magma) &cat[Reverse(IntegerToSequence(n, 9)):n in[1..31]]; // Jason Kimberley, Dec 07 2012
(Haskell)
a031076 n = a031076_list !! (n-1)
a031076_list = concat $ map reverse $ tail a031087_tabf
-- Reinhard Zumkeller, Jul 07 2015
(Python)
from itertools import count, chain, islice
from sympy.ntheory.factor_ import digits
def A031076_gen(): return chain.from_iterable(digits(m, 9)[1:] for m in count(1))
A031076_list = list(islice(A031076_gen(), 30)) # Chai Wah Wu, Jan 07 2022
CROSSREFS
Tables in which the n-th row lists the base b digits of n: A030190 and A030302 (b=2), A003137 and A054635 (b=3), A030373 (b=4), A031219 (b=5), A030548 (b=6), A030998 (b=7), A031035 and A054634 (b=8), this sequence (b=9), A007376 and A033307 (b=10). - Jason Kimberley, Dec 06 2012
Sequence in context: A265524 A256299 A256289 * A346732 A321999 A228822
KEYWORD
nonn,base,cons,easy,tabf
STATUS
approved