This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A033046 #50 Aug 06 2024 21:22:21 %S A033046 0,1,9,10,81,82,90,91,729,730,738,739,810,811,819,820,6561,6562,6570, %T A033046 6571,6642,6643,6651,6652,7290,7291,7299,7300,7371,7372,7380,7381, %U A033046 59049,59050,59058,59059,59130,59131,59139,59140,59778,59779,59787 %N A033046 Sums of distinct powers of 9. %C A033046 Numbers without any base-9 digits greater than 1. %C A033046 a(n) modulo 2 is the Prouhet-Thue-Morse sequence A010060. - _Philippe Deléham_, Oct 17 2011 %H A033046 T. D. Noe, <a href="/A033046/b033046.txt">Table of n, a(n) for n = 0..1023</a> %H A033046 Hsien-Kuei Hwang, Svante Janson, and Tsung-Hsi Tsai, <a href="https://arxiv.org/abs/2210.10968">Identities and periodic oscillations of divide-and-conquer recurrences splitting at half</a>, arXiv:2210.10968 [cs.DS], 2022, p. 45. %F A033046 a(n) = Sum_{i=0..m} d(i)*9^i, where Sum_{i=0..m} d(i)*2^i is the base-2 representation of n. %F A033046 a(n) = A097255(n)/8. %F A033046 a(2n) = 9*a(n), a(2n+1) = a(2n)+1. %F A033046 a(n) = Sum_{k>=0} A030308(n,k)*9^k. - _Philippe Deléham_, Oct 17 2011 %F A033046 G.f.: (1/(1 - x))*Sum_{k>=0} 9^k*x^(2^k)/(1 + x^(2^k)). - _Ilya Gutkovskiy_, Jun 04 2017 %t A033046 FromDigits[#,9]&/@Tuples[{1,0},6]//Sort (* _Harvey P. Dale_, Sep 05 2017 *) %o A033046 (PARI) A033046(n,b=9)=subst(Pol(binary(n)),'x,b) \\ _M. F. Hasler_, Feb 01 2016 %Y A033046 Cf. A000695, A005836, A033043-A033052. %Y A033046 Row 9 of array A104257. %K A033046 nonn,base,easy %O A033046 0,3 %A A033046 _Clark Kimberling_ %E A033046 Extended by _Ray Chandler_, Aug 03 2004