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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.

A254046 Column index of n in A191450: a(3n) = 1, a(3n+1) = 1, a(3n+2) = 1 + a(n+1).

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%I A254046 #43 Nov 16 2023 07:44:39
%S A254046 1,2,1,1,3,1,1,2,1,1,2,1,1,4,1,1,2,1,1,2,1,1,3,1,1,2,1,1,2,1,1,3,1,1,
%T A254046 2,1,1,2,1,1,5,1,1,2,1,1,2,1,1,3,1,1,2,1,1,2,1,1,3,1,1,2,1,1,2,1,1,4,
%U A254046 1,1,2,1,1,2,1,1,3,1,1,2,1,1,2,1,1,3,1,1,2,1,1,2,1,1,4,1,1,2,1,1,2,1,1,3,1,1,2,1,1,2,1,1,3,1,1,2,1,1,2,1,1,6,1,1,2,1,1,2
%N A254046 Column index of n in A191450: a(3n) = 1, a(3n+1) = 1, a(3n+2) = 1 + a(n+1).
%C A254046 Equally, the row index of n in A254051.
%C A254046 a(n) is the 3-adic valuation of A087289(n-1). - _Fred Daniel Kline_, Jan 11 2017
%H A254046 Antti Karttunen, <a href="/A254046/b254046.txt">Table of n, a(n) for n = 1..9842</a>
%F A254046 a(3n) = 1, a(3n+1) = 1, a(3n+2) = 1 + a(n+1).
%F A254046 a(n) = A253786(n) + 1.
%F A254046 a(n) = A253786(3n-1). - _Cyril Damamme_, Aug 04 2015
%F A254046 a(n) = A051064(2n-1), i.e., the 3-adic valuation of 6n-3. - _Cyril Damamme_, Aug 04 2015
%F A254046 Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k) = 3/2. - _Amiram Eldar_, Nov 16 2023
%t A254046 With[{nmax=200},IntegerExponent[6Range[nmax]-3,3]] (* _Paolo Xausa_, Nov 10 2023 *)
%o A254046 (Scheme, with memoization-macro definec)
%o A254046 (definec (A254046 n) (if (= 2 (modulo n 3)) (+ 1 (A254046 (/ (+ 1 n) 3))) 1))
%Y A254046 One more than A253786.
%Y A254046 Cf. A253887 (the corresponding row index).
%Y A254046 Cf. A191450, A254047, A254051, A254052.
%Y A254046 Odd bisection of A051064.
%Y A254046 Cf. A007949, A087289.
%K A254046 nonn,easy
%O A254046 1,2
%A A254046 _Antti Karttunen_, Jan 24 2015