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The (2^n)-th lucky number.
1

%I #17 Sep 10 2024 15:40:01

%S 1,3,9,25,67,151,349,805,1831,4069,9063,19767,42975,92829,199123,

%T 425229,904225,1915381,4044235,8513505,17872759,37432615,78225409,

%U 163146639,339638307,705882493,1464816541,3035420871,6281814787,12984437515,26808298093,55291335127

%N The (2^n)-th lucky number.

%H Dana Jacobsen, <a href="/A181383/b181383.txt">Table of n, a(n) for n = 0..43</a>

%F a(n) = A000959(2^n) = A000959(A000079(n)).

%t t = 2 Range@9000000 - 1; f[n_] := Block[{k = t[[n]]}, t = Delete[t, Table[{k}, {k, k, Length@t, k}]]]; Do[f@n, {n, 2, 100000}]; Table[ t[[2^n]], {n, 0, 20}]

%o (Perl) use ntheory ":all"; say "$_ ",nth_lucky(1 << $_) for 0..25; # _Dana Jacobsen_, Dec 21 2018

%Y Cf. A000079, A000959, A181382.

%K hard,nonn

%O 0,2

%A _Robert G. Wilson v_, Oct 16 2010

%E a(21)-a(25) from _Donovan Johnson_, Oct 16 2010

%E a(26)-a(31) from _Dana Jacobsen_, Dec 21 2018