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Natural numbers with number of divisors not equal to a Lucas number.
2

%I #9 Oct 07 2019 11:03:00

%S 12,16,18,20,24,28,30,32,36,40,42,44,45,48,50,52,54,56,60,63,66,68,70,

%T 72,75,76,78,80,81,84,88,90,92,96,98,99,100,102,104,105,108,110,112,

%U 114,116,117,120,124,126,128,130,132,135,136,138,140,144,147,148

%N Natural numbers with number of divisors not equal to a Lucas number.

%H Amiram Eldar, <a href="/A119911/b119911.txt">Table of n, a(n) for n = 1..10000</a>

%t With[{lnos=LucasL[Range[0,20]]},Select[Range[300],!MemberQ[ lnos, DivisorSigma[ 0,#]]&]] (* _Harvey P. Dale_, May 11 2014 *)

%Y Cf. A000032.

%Y Complement to A119885.

%K easy,nonn

%O 1,1

%A _Giovanni Teofilatto_, Aug 02 2006

%E More terms from _Harvey P. Dale_, May 11 2014