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a(n) = Lucas(prime(n)).
8

%I #49 Sep 08 2022 08:45:54

%S 3,4,11,29,199,521,3571,9349,64079,1149851,3010349,54018521,370248451,

%T 969323029,6643838879,119218851371,2139295485799,5600748293801,

%U 100501350283429,688846502588399,1803423556807921,32361122672259149,221806434537978679

%N a(n) = Lucas(prime(n)).

%C This is to A030426, Fibonacci(prime(n)), as A000032 (Lucas numbers beginning at 2) is to A000045.

%H <a href="/A180363/b180363.txt">Table of n, a(n) for n = 1..650</a>

%H A. Aksenov, <a href="http://arxiv.org/abs/1108.5352">The Newman phenomenon and Lucas sequence</a>, arXiv:1108.5352 [math.NT], 2011. [Gives factorizations of first 88 terms]

%H Paula Burkhardt et al., <a href="http://arxiv.org/abs/1505.00018">Visual properties of generalized Kloosterman sums</a>, arXiv:1505.00018 [math.NT], 2015.

%F a(n) = A000032(A000040(n)) = Lucas(prime(n)).

%F a(n) = A032170(A000040(n)) / A064723(n-1) - 1 for n>1. - _Flávio V. Fernandes_, Dec 30 2021

%e a(1) = 3 because the 1st prime is 2, and the 2nd Lucas number is A000032(2) = 3.

%e a(2) = 4 because the 2nd prime is 3, and the 3rd Lucas number is A000032(3) = 4.

%e a(3) = 11 because the 3rd prime is 5, and the 5th Lucas number is A000032(5) = 11.

%p A180363 := proc(n) A000032(ithprime(n)) ; end proc: seq(A180363(n),n=1..30) ; # _R. J. Mathar_, Sep 01 2010

%p # second Maple program:

%p a:= n-> (<<1|1>, <1|0>>^ithprime(n). <<2, -1>>)[1, 1]:

%p seq(a(n), n=1..50); # _Alois P. Heinz_, Jan 03 2022

%t LucasL[Prime[Range[30]]] (* _Vincenzo Librandi_, Dec 01 2015 *)

%o (Magma) [Lucas(NthPrime(n)): n in [1..30]]; // _Vincenzo Librandi_, Dec 01 2015

%o (Python)

%o from sympy import lucas, prime

%o def a(n): return lucas(prime(n))

%o print([a(n) for n in range(1, 24)]) # _Michael S. Branicky_, Dec 30 2021

%Y Cf. A000032, A000040, A000045, A030426.

%K easy,nonn

%O 1,1

%A _Jonathan Vos Post_, Aug 31 2010

%E Entries checked by _R. J. Mathar_, Sep 01 2010

%E Edited by _N. J. A. Sloane_, Nov 28 2011