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%I #9 Sep 16 2022 15:25:53
%S 1,3,7,11,29,47,76,199,322,2207,24476,1149851,141422324,969323029,
%T 2537720636,10749957122,73681302247,119218851371,312119004989,
%U 505019158607,2139295485799,3461452808002,5600748293801,100501350283429
%N Lucas numbers for which the sum of the digits is a prime.
%H Chai Wah Wu, <a href="/A117790/b117790.txt">Table of n, a(n) for n = 1..720</a>
%e 199 is in the sequence because (1) it is a Lucas number and (2) the sum of its digits 1+9+9=19 is a prime number.
%t Join[{1},Select[LucasL[Range[100]],PrimeQ[Total[IntegerDigits[#]]]&]] (* _Harvey P. Dale_, Sep 16 2022 *)
%o (Python)
%o from sympy import isprime
%o A117790_list, a, b = [1], 1, 3
%o for _ in range(10**6):
%o if isprime(sum(int(d) for d in str(b))):
%o A117790_list.append(b)
%o a, b = b, a+b # _Chai Wah Wu_, Dec 25 2015
%Y Cf. A000204.
%K base,nonn
%O 1,2
%A Luc Stevens (lms022(AT)yahoo.com), Apr 15 2006
%E a(6) corrected by _Klaus Brockhaus_, Apr 17 2006
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