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A129098 a(n) = A129095(2^n + 2^(n-1) - 1) for n>=1. 4

%I

%S 1,5,23,135,1119,14319,300015,10636463,652217135,70382845743,

%T 13551477257519,4706105734658351,2973879284783561007,

%U 3444999327807280048431,7362415635261959807011119,29188908702092573515760044335

%N a(n) = A129095(2^n + 2^(n-1) - 1) for n>=1.

%C b(n)=A129095(n) obeys the recurrence: b(n) = b(n/2) (n even), b(n) = 2*b(n-1) + b(n-2) (n odd >1), with b(1) = 1.

%t Block[{e = 18, s}, s = Nest[Append[#1, If[EvenQ[#2], #1[[#2/2]], 2 #1[[-1]] + #1[[-2]] ] ] & @@ {#, Length@ # + 1} &, {1}, 2^e]; Array[s[[2^# + 2^(# - 1) - 1]] &, e - 1]] (* _Michael De Vlieger_, Mar 10 2020 *)

%o (PARI)

%Y Cf. A129095, A129096, A129097, A129099.

%K easy,nonn

%O 1,2

%A _Paul D. Hanna_, Apr 11 2007

%E a(16) from _Michael De Vlieger_, Mar 10 2020.

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Last modified January 20 08:12 EST 2021. Contains 340301 sequences. (Running on oeis4.)