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%I #51 Dec 08 2020 03:49:28
%S 13,169,221,247,299,377,403,481,533,559,611,689,767,793,871,923,949,
%T 1027,1079,1157,1261,1313,1339,1391,1417,1469,1651,1703,1781,1807,
%U 1937,1963,2041,2119,2171,2197,2249,2327,2353,2483,2509,2561,2587,2743,2873
%N Numbers whose smallest prime factor is 13.
%H Amiram Eldar, <a href="/A084970/b084970.txt">Table of n, a(n) for n = 1..10000</a>
%H <a href="/index/Rec#order_481">Index entries for linear recurrences with constant coefficients</a>, order 481.
%F a(n) = a(n-480) + 30030 = a(n-1) + a(n-480) - a(n-481). - _Charles R Greathouse IV_, Nov 19 2014
%F Lim_{n->infinity} a(n)/n = A038111(6)/A038110(6) = 1001/16 = 62.5625. - _Vladimir Shevelev_, Jan 20 2015
%F a(n) = 13*A008365(n).
%e a(2) = 13*13, a(3) = 13*17.
%t Select[ 13Range@ 225, GCD[#, 2310] == 1 &] (* _Robert G. Wilson v_, Dec 18 2014 *)
%o (PARI) is(n)=n%13==0 && gcd(n,2310)==1 \\ _Charles R Greathouse IV_, Nov 19 2014
%Y Sixth row of A083140.
%Y Cf. A084967 (5), A084968 (7), A084969 (11), A332799 (17), A332798 (19), A332797 (23), A008365 (13-rough numbers).
%K nonn,easy
%O 1,1
%A _Robert G. Wilson v_, Jun 15 2003
%E More terms from _David Wasserman_, Oct 19 2004
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