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%I #16 Aug 27 2024 01:29:16
%S 0,2,5,4,8,6,9,8,13,10,13,12,16,14,17,16,22,18,21,20,24,22,25,24,29,
%T 26,29,28,32,30,33,32,39,34,37,36,40,38,41,40,45,42,45,44,48,46,49,48,
%U 54,50,53,52,56,54,57,56,61,58,61,60,64,62,65,64,72,66,69,68,72
%N Exponent of 2 in 6^n - 2^n.
%F Recurrence: a(2n) = a(n) + [(n+1)/2] + 1, a(2n+1) = 2n+2.
%F a(n) = n + A007814(A024023(n)) = n + A090740(n). - _Reinhard Zumkeller_, Mar 27 2004
%t Join[{0},Table[IntegerExponent[6^n-2^n,2],{n,70}]] (* _Harvey P. Dale_, Mar 08 2012 *)
%o (PARI) a(n)=if(n<1,0,if(n%2==0,a(n/2)+2*floor((n+2)/4)+1,n+1))
%o (Python)
%o def A093052(n): return n+(~(m:=3**n-1)& m-1).bit_length() if n else 0 # _Chai Wah Wu_, Jul 07 2022
%Y a(n-1) is the exponent of 2 in A009168(n), A012394(n), A088991(n), A009083(n), A012036(n), A012092(n), A012395(n), A012460(n), A012465(n), A012466(n), A012467(n), (A049294(n)-1)/3.
%Y Cf. A093050, A093051.
%K nonn
%O 0,2
%A _Ralf Stephan_, Mar 16 2004
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