A005371 a(n) = L(L(n)), where L(n) are Lucas numbers A000032.

3, 1, 4, 7, 29, 199, 5778, 1149851, 6643838879, 7639424778862807, 50755107359004694554823204, 387739824812222466915538827541705412334749, 19679776435706023589554719270187913247121278789615838446937339578603

Offset: 0

Author

N. J. A. Sloane

Keywords

• easy
• nonn

References

• T. Koshy (2001), Fibonacci and Lucas Numbers with Applications, John Wiley & Sons, New York, 511-516
• N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

• T. D. Noe, Table of n, a(n) for n = 0..15

Crossrefs

Cf. A000032, A005372, A007570, A068096, A068098.

Programs

Magma

[ Lucas(Lucas(n)): n in [0..20]]; // Vincenzo Librandi, Apr 16 2011

Maple

L:= n-> (<<0|1>, <1|1>>^n. <<2,1>>)[1,1]:
a:= n-> L(L(n)):
seq(a(n), n=0..14);  # Alois P. Heinz, Jun 01 2016

Mathematica

l[n_]:= l[n]= l[n-1] + l[n-2]; l[0]= 2; l[1]= 1; Table[l[l[n]], {n,0,12}]
LucasL[LucasL[Range[0, 15]]] (* G. C. Greubel, Dec 21 2017 *)

PARI

{lucas(n) = fibonacci(n+1) + fibonacci(n-1)};
for(n=0,15, print1(lucas(lucas(n)), ", ")) \\ G. C. Greubel, Dec 21 2017

SageMath

[lucas_number2(lucas_number2(n, 1,-1),1,-1) for n in range(15)] # G. C. Greubel Nov 14 2022

Extensions

More terms from Mario Catalani (mario.catalani(AT)unito.it), Mar 14 2003

Offset changed Feb 28 2007