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A129097
a(n) = A129095(2^n - 1) for n>=1.
4
1, 3, 11, 51, 323, 3075, 47427, 1230787, 54772163, 4247022531, 582413946819, 143061847179203, 63604391931367363, 51621812365091401667, 77028054123935294320579, 212592144046864728487817155
OFFSET
1,2
COMMENTS
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.
MATHEMATICA
Block[{e = 16, s}, s = Nest[Append[#1, If[EvenQ[#2], #1[[#2/2]], 2 #1[[-1]] + #1[[-2]] ] ] & @@ {#, Length@ # + 1} &, {1}, 2^e]; Array[s[[2^# - 1]] &, e]] (* Michael De Vlieger, Mar 10 2020 *)
PROG
(PARI)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul D. Hanna, Apr 11 2007
STATUS
approved