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A124979 Numbers in A118882 for which 5 is not a divisor.

%I A124979 #16 Sep 11 2022 00:40:12
%S A124979 169,221,289,338,377,442,481,493,533,578,629,676,689,697,754,793,841,
%T A124979 884,901,949,962,986,1037,1066,1073,1156,1157,1189,1241,1258,1261,
%U A124979 1313,1352,1369,1378,1394,1417,1469,1508,1513,1517
%N A124979 Numbers in A118882 for which 5 is not a divisor.
%H A124979 Andrew Howroyd, <a href="/A124979/b124979.txt">Table of n, a(n) for n = 1..5300</a>
%o A124979 (Python)
%o A124979 from itertools import count, islice
%o A124979 from math import prod
%o A124979 from sympy import factorint
%o A124979 def A124979_gen(startvalue=1): # generator of terms >= startvalue
%o A124979     for n in count(max(startvalue,1)):
%o A124979         f = factorint(n)
%o A124979         if n%5 and 1<int(not any(e&1 for e in f.values())) + (((m:=prod(1 if p==2 else (e+1 if p&3==1 else (e+1)&1) for p, e in f.items()))+((((~n & n-1).bit_length()&1)<<1)-1 if m&1 else 0))>>1):
%o A124979             yield n
%o A124979 A124979_list = list(islice(A124979_gen(),30)) # _Chai Wah Wu_, Sep 09 2022
%Y A124979 Cf. A118882.
%K A124979 nonn
%O A124979 1,1
%A A124979 _Artur Jasinski_, Nov 15 2006
%E A124979 Corrected and extended by _M. F. Hasler_, Feb 08 2009
%E A124979 Further corrections following an observation by P. McNab, by _M. F. Hasler_, Jul 08 2015