%I #19 Oct 22 2021 23:49:40
%S 5,7,9,10,11,13,14,15,16,17,18,19,20,21,22,23,25,26,27,28,29,30,31,32,
%T 33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51,52,53,54,55,
%U 56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77
%N Numbers not dividing 24.
%C These terms m > 5 can be called "triphile" or "3-phile" numbers, because there are 3 positive integers b_1 < b_2 < b_3 such that b_1 divides b_2, b_2 divides b_3 and m = b_1 + b_2 + b_3. A number that is not "triphile" is called "triphobe" or "3-phobe" (A019532). The smallest triphile number is 7 = 1 + 2 + 4 and the largest triphobe is 24. See A348517 for more explanations and link. - _Bernard Schott_, Oct 21 2021
%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>
%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/polprdipi.jpg">Divisors and pi(x)</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).
%F a(n) = n + 8 for n > 16. [_Charles R Greathouse IV_, Oct 26 2011]
%t Complement[Range[100],Divisors[24]] (* _Harvey P. Dale_, May 13 2019 *)
%o (PARI) is(n)=!!n%24 \\ _Charles R Greathouse IV_, Oct 26 2011
%Y Complement of A018253.
%Y Cf. A000005, A000720, A161205.
%Y Cf. A019532, A348517.
%K easy,nonn
%O 1,1
%A _Omar E. Pol_, Jun 19 2009, Jun 28 2009
%E Definition corrected by _Omar E. Pol_, Nov 17 2009