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A037477 a(n) = Sum{d(i)*9^i: i=0,1,...,m}, where Sum{d(i)*8^i: i=0,1,...,m} is the base 8 representation of n.

%I A037477 #35 Jan 27 2025 18:45:20
%S A037477 0,1,2,3,4,5,6,7,9,10,11,12,13,14,15,16,18,19,20,21,22,23,24,25,27,28,
%T A037477 29,30,31,32,33,34,36,37,38,39,40,41,42,43,45,46,47,48,49,50,51,52,54,
%U A037477 55,56,57,58,59,60,61,63,64,65,66,67,68,69,70,81,82,83,84,85
%N A037477 a(n) = Sum{d(i)*9^i: i=0,1,...,m}, where Sum{d(i)*8^i: i=0,1,...,m} is the base 8 representation of n.
%C A037477 Numbers that do not contain the digit 8 in their base 9 expansion. - _M. F. Hasler_, Oct 05 2014
%H A037477 François Marques, <a href="/A037477/b037477.txt">Table of n, a(n) for n = 0..10000</a> (first 1000 terms from Clark Kimberling)
%F A037477 For n<64, a(n) = floor(9n/8) = A248375(n). - _M. F. Hasler_, Oct 05 2014
%e A037477 a(63) = 7*9+7 = 70 since 63 = 77[8], i.e., "77" when written in base 8;
%e A037477 a(64) = 1*9^2 = 81 since 64 = 100[8]. - _M. F. Hasler_, Oct 05 2014
%t A037477 Table[FromDigits[RealDigits[n, 8], 9], {n, 0, 100}]
%t A037477 Select[Range[0,100],DigitCount[#,9,8]==0&] (* _Harvey P. Dale_, Aug 06 2024 *)
%o A037477 (PARI) a(n) = vector(#n=digits(n,8),i,9^(#n-i))*n~ \\ _M. F. Hasler_, Oct 05 2014
%o A037477 (PARI) a(n) = fromdigits(digits(n, 8), 9); \\ _François Marques_, Oct 15 2020
%o A037477 (Python)
%o A037477 def A037477(n): return int(oct(n)[2:],9) # _Chai Wah Wu_, Jan 27 2025
%Y A037477 Cf. A248375.
%Y A037477 Cf. Numbers with at least one digit b-1 in base b : A074940 (b=3), A337250 (b=4), A337572 (b=5), A333656 (b=6), A337141 (b=7), A337239 (b=8), A338090 (b=9), A011539 (b=10), A095778 (b=11).
%Y A037477 Cf. Numbers with no digit b-1 in base b: A005836 (b=3), A023717 (b=4), A020654 (b=5), A037465 (b=6), A020657 (b=7), A037474 (b=8), this sequence (b=9), A007095 (b=10), A171397 (b=11).
%K A037477 nonn,base,easy
%O A037477 0,3
%A A037477 _Clark Kimberling_
%E A037477 Offset changed to 0 by _Clark Kimberling_, Aug 14 2012