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A073789 Numbers in base -8. 10
0, 1, 2, 3, 4, 5, 6, 7, 170, 171, 172, 173, 174, 175, 176, 177, 160, 161, 162, 163, 164, 165, 166, 167, 150, 151, 152, 153, 154, 155, 156, 157, 140, 141, 142, 143, 144, 145, 146, 147, 130, 131, 132, 133, 134, 135, 136, 137, 120, 121, 122, 123, 124, 125, 126 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

REFERENCES

D. E. Knuth, The Art of Computer Programming. Addison-Wesley, Reading, MA, 1969, Vol. 2, p. 189.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Prepared and presented by Matthew Szudzik of Wolfram Research, A Mathematica programming contest

Eric Weisstein's World of Mathematics, Negabinary

Wikipedia, Negative base

MATHEMATICA

ToNegaBases[i_Integer, b_Integer] := FromDigits[ Rest[ Reverse[ Mod[ NestWhileList[(#1 - Mod[ #1, b])/-b &, i, #1 != 0 &], b]]]]; Table[ ToNegaBases[n, 8], {n, 0, 60}]

PROG

(Haskell)

a073789 0 = 0

a073789 n = a073789 n' * 10 + m where

   (n', m) = if r < 0 then (q + 1, r + 8) else (q, r)

             where (q, r) = quotRem n (negate 8)

-- Reinhard Zumkeller, Jul 07 2012

(Python)

def A073789(n):

    s, q = '', n

    while q >= 8 or q < 0:

        q, r = divmod(q, -8)

        if r < 0:

            q += 1

            r += 8

        s += str(r)

    return int(str(q)+s[::-1]) # Chai Wah Wu, Apr 09 2016

CROSSREFS

Cf. A007094, A039724, A073785, A007608, A073786, A073787, A073788, A073790 & A039723.

Sequence in context: A115916 A065667 A099146 * A004880 A065666 A240466

Adjacent sequences:  A073786 A073787 A073788 * A073790 A073791 A073792

KEYWORD

base,easy,nonn

AUTHOR

Robert G. Wilson v, Aug 11 2002

STATUS

approved

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Last modified February 19 18:31 EST 2018. Contains 299356 sequences. (Running on oeis4.)