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%I #32 Apr 10 2019 21:43:48
%S 121,143,169,187,209,221,247,253,289,299,319,323,341,361,377,391,403,
%T 407,437,451,473,481,493,517,527,529,533,551,559,583,589,611,629,649,
%U 667,671,689,697,703,713,731,737,767,779,781,793,799,803,817,841,851
%N Composite numbers with smallest prime factor >= 11.
%C Composite n such that n^6 is congruent to {1, 169} mod 210. All primes > 7 satisfy this condition. - _Gary Detlefs_, Dec 09 2012
%H T. D. Noe, <a href="/A038511/b038511.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) ~ 4.375n. - _Charles R Greathouse IV_, Dec 10 2012
%p for n from 1 to 1000 do if (n^6 mod 210 = 1 or n^6 mod 210 = 169) and not isprime(n) then print(n) fi od; # _Gary Detlefs_, Dec 09 2012
%t Select[Range[1000], Not[PrimeQ[#]] && FactorInteger[#][[1, 1]] > 7 &] (* _Alonso del Arte_, Dec 09 2012 *)
%o (PARI) is(n)=gcd(210,n)==1 && !isprime(n) \\ _Charles R Greathouse IV_, Dec 10 2012
%o (GAP) Filtered([11..1000],n->(PowerMod(n,6,210)=1 or PowerMod(n,6,210)=169) and not IsPrime(n)); # _Muniru A Asiru_, Nov 24 2018
%Y Cf. A008364.
%K nonn
%O 1,1
%A _Jeff Burch_
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