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A249876 Pseudo-lucky numbers.

%I A249876 #22 Feb 26 2024 19:17:25
%S A249876 1,3,5,7,11,13,17,21,23,25,31,35,41,43,45,47,55,57,63,65,73,75,83,87,
%T A249876 95,97,101,105,107,113,123,127,131,133,141,143,147,151,153,161,175,
%U A249876 177,183,185,197,201,211,213,215,217,227,233,235,237,251,255,265,267
%N A249876 Pseudo-lucky numbers.
%C A249876 Appears to grow more slowly than the Lucky numbers. - _Jon Perry_, Nov 07 2014
%H A249876 Jean-François Alcover, <a href="/A249876/b249876.txt">Table of n, a(n) for n = 1..1000</a>
%e A249876 Start with the natural numbers. The 2nd number is 2, so delete every 2nd number, leaving 1 3 5 7 9 11 13 15 17 19...; the 3rd number remaining is 5, so delete every 5th number, leaving 1 3 5 7 11 13 15 17 ...; now delete every 7th number, leaving 1 3 5 7 11 13 17 ...; now delete every 11th number; etc.
%p A249876 L:= [seq(i, i=1..10^3)]:
%p A249876 for n from 2 while n < nops(L) do
%p A249876   r:= L[n];
%p A249876   L:= subsop(seq(r*i=NULL, i=1..nops(L)/r), L);
%p A249876 od:
%p A249876 L;
%t A249876 FixedPoint[Function[{L}, n++; Delete[L, List /@ (L[[n]]*Range[Quotient[Length[L], L[[n]] ]])]], n=1; Range[1000]] (* _Jean-François Alcover_, Nov 27 2014 *)
%o A249876 (Python)
%o A249876 def listed(n):
%o A249876    L=list(range(1,n+1));j=1
%o A249876    while L[j] <= len(L):
%o A249876       L=[L[i] for i in range(len(L)) if (i+1)%L[j]!=0]
%o A249876       j+=1
%o A249876    return(L)
%Y A249876 Cf. A000959 (Lucky numbers).
%K A249876 nonn
%O A249876 1,2
%A A249876 _Robert FERREOL_, Nov 07 2014