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 A269265 a(0) = a(1) = 1; thereafter a(n) = a(n-1) + a(n-2) if n is even, otherwise a(n) = a(n-1)^2. 0
 1, 1, 2, 4, 6, 36, 42, 1764, 1806, 3261636, 3263442, 10650053687364, 10650056950806, 113423713055411194304049636, 113423713055421844361000442, 12864938683278671740537145884937248491231415124195364, 12864938683278671740537145998360961546653259485195806 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS The first bisection is A007018, the second bisection is A174864 (with an only initial 1). After 2, all terms belong to A238411. LINKS FORMULA a(n) = ( 1 + Sum_{k=0..floor(n/2)-1} a(2*k+1) )^(3-(-1)^n)/2 for n>1. MATHEMATICA a[n_] := If[OddQ@n, a[n - 1] + a[n - 2], a[n - 1]^2]; a[0] = 1; Array[a, 17] PROG (MAGMA) [n le 2 select 1 else IsEven(n) select Self(n-1)^2 else Self(n-1)+Self(n-2): n in [1..20]]; CROSSREFS Cf. A007018, A174864, A238411. Sequence in context: A045662 A195324 A175877 * A173818 A263541 A283157 Adjacent sequences:  A269262 A269263 A269264 * A269266 A269267 A269268 KEYWORD nonn AUTHOR Vincenzo Librandi, Feb 23 2016 EXTENSIONS Edited and extended by Bruno Berselli, Feb 25 2016 STATUS approved

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Last modified September 27 12:40 EDT 2021. Contains 347688 sequences. (Running on oeis4.)