# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a282181 Showing 1-1 of 1 %I A282181 #12 Sep 08 2022 08:46:18 %S A282181 9,702,345946302,41402453463588423862656702, %T A282181 70970560162990674076135964501350282214065161983319841388247466125133356250302 %N A282181 a(n+1) = a(n)*(a(n)^2 - 3) with a(0) = 9. %H A282181 E. B. Escott, Rapid method for extracting a square root, Amer. Math. Monthly, 44 (1937), 644-646. %F A282181 a(n) = ((9 + sqrt(77))/2)^(3^n) + ((9 - sqrt(77))/2)^(3^n). - _Bruno Berselli_, Feb 10 2017 %t A282181 RecurrenceTable[{a[0] == 9, a[n] == a[n-1]^3 - 3 a[n-1]}, a, {n, 8}] %o A282181 (Magma) [n eq 1 select 9 else Self(n-1)^3-3*Self(n-1): n in [1..6]]; %Y A282181 Cf. similar sequences listed in A282180. %K A282181 nonn %O A282181 0,1 %A A282181 _Vincenzo Librandi_, Feb 10 2017 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE