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%I #28 Apr 01 2021 14:54:08
%S 4,1,7,29,1149851,387739824812222466915538827541705412334749
%N a(n) = L(L(L(n))), where L(n) are Lucas numbers A000032.
%C a(6) = 3393011755..4322744978 has 1208 decimal digits and a(7) = 4437405101..8830136999 has 240305 decimal digits.
%H Alois P. Heinz, <a href="/A262361/b262361.txt">Table of n, a(n) for n = 0..5</a>
%p L:= n-> (<<0|1>, <1|1>>^n. <<2, 1>>)[1$2]:
%p a:= n-> L(L(L(n))):
%p seq(a(n), n=0..5);
%t A262361 = Nest[LucasL, #, 3] &; Array[A262361, 6, 0] (* _JungHwan Min_, Nov 09 2016 *)
%o (Python)
%o from sympy import lucas as L
%o def a(n): return L(L(L(n)))
%o print([a(n) for n in range(6)]) # _Michael S. Branicky_, Apr 01 2021
%Y Cf. A000032, A005371, A058051.
%K nonn
%O 0,1
%A _Alois P. Heinz_, Nov 09 2016
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