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%I #15 Jun 20 2019 17:43:51
%S 1,2,4,2,4,8,4,8,13,2,4,8,4,8,16,8,16,26,4,8,13,8,16,26,13,26,40,2,4,
%T 8,4,8,16,8,16,26,4,8,16,8,16,32,16,32,52,8,16,26,16,32,52,26,52,80,4,
%U 8,13,8,16,26,13,26,40,8,16,26,16,32,52,26,52,80,13
%N a(n) = sum_{k=0..n} (C(n,k) mod 3).
%C Row sums of the triangle in A083093. - _Reinhard Zumkeller_, Jul 11 2013
%H Reinhard Zumkeller, <a href="/A051638/b051638.txt">Table of n, a(n) for n = 0..6561=3^8</a>
%H Michael Gilleland, <a href="/selfsimilar.html">Some Self-Similar Integer Sequences</a>
%H A. Granville, <a href="http://www.dms.umontreal.ca/~andrew/Binomial/intro.html">Binomials modulo a prime</a>
%F Write n in base 3; if the representation contains r 1's and s 2's then a(n) = 2^{r-1} * (3^(s+1) - 1) = 1/2 * (3*A006047(n) - 2^(A062756(n))). - _Robin Chapman_, Ahmed Fares (ahmedfares(AT)my-deja.com) and others, Jul 16 2001
%t Table[2^(DigitCount[n,3,1]-1) (3^(DigitCount[n,3,2]+1)-1),{n,0,80}] (* _Harvey P. Dale_, Jun 20 2019 *)
%o (Haskell)
%o a051638 = sum . a083093_row -- _Reinhard Zumkeller_, Jul 11 2013
%Y Cf. A001316.
%K nonn
%O 0,2
%A _N. J. A. Sloane_
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