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%I #17 Apr 03 2024 15:16:59
%S 0,0,0,0,0,1,0,1,0,0,1,0,0,1,1,1,0,0,0,0,1,1,0,1,0,0,1,0,1,1,1,1,0,0,
%T 0,0,0,1,0,1,1,0,1,0,0,1,1,1,0,0,0,0,1,1,0,1,1,0,1,0,1,1,1,1,0,0,0,0,
%U 0,1,0,1,0,0,1,0,0,1,1,1,1,0,0,0,1,1,0,1,0,0,1,0,1,1,1,1,0,0,0,0,0,1,0,1,1
%N Bit that is two places to left of least significant 1-bit in the binary expansion of n.
%H Kevin Ryde, <a href="/A086483/b086483.txt">Table of n, a(n) for n = 0..8192</a>
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%e For n = 4, 5, 6, 7, 8 the binary expansions are 100, 101, 110, 111, 1000 and the values of a(n) are respectively 0, 1, 0, 1, 0.
%t Join[{0}, Array[BitGet[#, IntegerExponent[#, 2] + 2] &, 100]] (* _Paolo Xausa_, Apr 02 2024 *)
%o (PARI) a(n) = bittest(n, if(n,valuation(n,2)+2)); \\ _Kevin Ryde_, Apr 07 2022
%Y Cf. A038189.
%K nonn,easy
%O 0,1
%A _N. J. A. Sloane_, Dec 22 2003
%E Corrected and extended by Douglas Gaut (dgaut(AT)ashland.edu), Apr 12 2004
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