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%I #17 Jan 03 2025 17:47:43
%S 1,2,3,4,6,10,42,48,56,66,70,86,108,126,134,214,248,459,1479,1722,
%T 3076,5064,5102,7602,9454,11361,11494,12450,16474,20139,32164,41013,
%U 42456,56307,79828,108506,136587
%N Numbers k such that k*Lucas(k) + 1 is prime.
%C a(38) > 2*10^5. - _Michael S. Branicky_, Jan 03 2025
%e If k =1 then k*Lucas(k) + 1 = 2 (prime).
%e If k = 66 then k*Lucas(k) + 1 = 4099474525767589 (prime).
%t Select[Range[9000],PrimeQ[# LucasL[#]+1]&] (* _Harvey P. Dale_, Nov 10 2011 *)
%Y Cf. A134313, A134580, A000032.
%K nonn,more
%O 1,2
%A _Parthasarathy Nambi_, Jan 27 2008
%E a(21)-a(24) from _Harvey P. Dale_, Nov 10 2011
%E a(25)-a(37) from _Michael S. Branicky_, Jan 02 2025