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A007095 Numbers in base 9.
(Formerly M0490)
307
0, 1, 2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50, 51, 52, 53, 54, 55, 56, 57, 58, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70, 71, 72, 73, 74, 75, 76, 77, 78, 80, 81, 82, 83, 84 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
Also numbers without 9 as a digit.
Complement of A011539: A102683(a(n)) = 0; A068505(a(n)) != a(n)). - Reinhard Zumkeller, Dec 29 2011
REFERENCES
Julian Havil, Gamma, Exploring Euler's Constant, Princeton University Press, Princeton and Oxford, 2003, page 34.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
M. F. Hasler, Numbers avoiding certain digits, OEIS wiki, Jan 12 2020
FORMULA
a(0) = 0, a(n) = 10*a(n/9) if n==0 (mod 9), a(n) = a(n-1)+1 otherwise. - Benoit Cloitre, Dec 22 2002
Sum_{n>1} 1/a(n) = A082838 = 22.92067... (Kempner series). - Bernard Schott, Dec 29 2018; edited by M. F. Hasler, Jan 13 2020
MAPLE
A007095 := proc(n) local l: if(n=0)then return 0: fi: l:=convert(n, base, 9): return op(convert(l, base, 10, 10^nops(l))): end: seq(A007095(n), n=0..67); # Nathaniel Johnston, May 06 2011
MATHEMATICA
Table[ FromDigits[ IntegerDigits[n, 9]], {n, 0, 75}]
PROG
(PARI) a(n)=if(n<1, 0, if(n%9, a(n-1)+1, 10*a(n/9)))
(PARI) A007095(n)=fromdigits(digits(n, 9)) \\ Michel Marcus, Dec 29 2018
(Magma) [ n: n in [0..74] | not 9 in Intseq(n) ]; // Bruno Berselli, May 28 2011
(sh) seq 0 1000 | grep -v 9; # Joerg Arndt, May 29 2011
(Haskell)
a007095 = f . subtract 1 where
f 0 = 0
f v = 10 * f w + r where (w, r) = divMod v 9
-- Reinhard Zumkeller, Oct 07 2014, Dec 29 2011
(Python) # and others: see OEIS Wiki page (cf. LINKS).
CROSSREFS
Cf. A000042 (base 1), A007088 (base 2), A007089 (base 3), A007090 (base 4), A007091 (base 5), A007092 (base 6), A007093 (base 7), A007094 (base 8); A057104, A037479.
Cf. A052382 (without 0), A052383 (without 1), A052404 (without 2), A052405 (without 3), A052406 (without 4), A052413 (without 5), A052414 (without 6), A052419 (without 7), A052421 (without 8).
Cf. A082838.
Sequence in context: A036741 A037479 A088481 * A194151 A020663 A255808
KEYWORD
nonn,easy,base
AUTHOR
STATUS
approved

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Last modified March 19 01:34 EDT 2024. Contains 370952 sequences. (Running on oeis4.)