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%I #10 Sep 19 2019 11:52:47
%S 2,1,3,11,322,1149851,425730551631123,
%T 208406472252232726621841472637412401,
%U 18490864749804416780204061487408593066264011288598603441079481989361240762271783793922
%N a(n) = L(P(n)), where L = Lucas numbers A000032, P = Pell numbers A000129.
%F a:= n-> (<<1|1>, <1|0>>^((<<2|1>, <1|0>>^n)[1, 2]). <<2, -1>>)[1, 1]:
%F seq(a(n), n=0..8); # _Alois P. Heinz_, Sep 19 2019
%t l[n_] := l[n] = l[n - 1] + l[n - 2]; l[0] = 2; l[1] = 1; p[n_] := p[n] = 2p[n - 1] + p[n - 2]; p[0] = 0; p[1] = 1; Table[l[p[n]], {n, 0, 8}]
%t LucasL[LinearRecurrence[{2,1},{0,1},10]] (* _Harvey P. Dale_, Sep 19 2019 *)
%Y Cf. A000032, A000129, A081322.
%K easy,nonn
%O 0,1
%A Mario Catalani (mario.catalani(AT)unito.it), Mar 18 2003
%E Typo in a(8) corrected by _Harvey P. Dale_, Sep 19 2019
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