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Nonludic numbers: complement of A003309.
24

%I #26 Dec 10 2021 07:23:52

%S 4,6,8,9,10,12,14,15,16,18,19,20,21,22,24,26,27,28,30,31,32,33,34,35,

%T 36,38,39,40,42,44,45,46,48,49,50,51,52,54,55,56,57,58,59,60,62,63,64,

%U 65,66,68,69,70,72,73,74,75,76,78,79,80,81,82,84,85,86,87

%N Nonludic numbers: complement of A003309.

%H Reinhard Zumkeller, <a href="/A192607/b192607.txt">Table of n, a(n) for n = 1..10000</a>

%F A192490(a(n)) = 0.

%t a3309[nmax_] := a3309[nmax] = Module[{t = Range[2, nmax], k, r = {1}}, While[Length[t] > 0, k = First[t]; AppendTo[r, k]; t = Drop[t, {1, -1, k}]]; r];

%t nmax = 1000;

%t Complement[Range[nmax], a3309[nmax]] (* _Jean-François Alcover_, Dec 10 2021, after _Ray Chandler_ in A003309 *)

%o (Haskell)

%o a192607 n = a192607_list !! (n-1)

%o a192607_list = filter ((== 0) . a192490) [1..]

%Y Cf. A192505 (not ludic but prime), A192506 (neither ludic nor prime).

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Jul 05 2011