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a(0) = 0, a(1) = 1, a(n) = a(n-2)*a(n-2) + 2 for n > 1.
4

%I #13 Apr 28 2014 23:56:51

%S 0,1,2,3,6,11,38,123,1446,15131,2090918,228947163,4371938082726,

%T 52416803445748571,19113842599189892819591078,

%U 2747521283470239265968814548542043,365338978906606237729724396156395693696687137202086

%N a(0) = 0, a(1) = 1, a(n) = a(n-2)*a(n-2) + 2 for n > 1.

%H Harry J. Smith, <a href="/A065653/b065653.txt">Table of n, a(n) for n=0,...,24</a>

%F A102847(n)=a(2n+1), A072191(n)=a(2n).

%t RecurrenceTable[{a[0]==0,a[1]==1,a[n]==a[n-2]^2+2},a,{n,20}] (* _Harvey P. Dale_, Aug 19 2013 *)

%o (PARI) a(n)=if(n<2, n>0, 2+a(n-2)^2) /* _Michael Somos_, Mar 25 2006 */

%o (PARI) { for (n=0, 24, if (n>1, a=a2^2 + 2; a2=a1; a1=a, if (n, a=a1=1, a=a2=0)); write("b065653.txt", n, " ", a) ) } \\ _Harry J. Smith_, Oct 25 2009

%Y Cf. A065652

%K nonn

%O 0,3

%A _Reinhard Zumkeller_, Nov 10 2001

%E One more term from _Harvey P. Dale_, Aug 19 2013

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Last modified September 23 08:14 EDT 2024. Contains 376146 sequences. (Running on oeis4.)