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Numbers whose smallest prime factor is 17.
6

%I #21 Sep 06 2023 13:41:19

%S 17,289,323,391,493,527,629,697,731,799,901,1003,1037,1139,1207,1241,

%T 1343,1411,1513,1649,1717,1751,1819,1853,1921,2159,2227,2329,2363,

%U 2533,2567,2669,2771,2839,2941,3043,3077,3247,3281,3349,3383,3587,3791,3859,3893

%N Numbers whose smallest prime factor is 17.

%C The asymptotic density of this sequence is 192/17017. - _Amiram Eldar_, Dec 06 2020

%D Emmanuel Desurvire, Classical and Quantum Information Theory: An Introduction for the Telecom Scientist, Cambridge University Press, 2009, table 20.5 p. 421.

%H Amiram Eldar, <a href="/A332799/b332799.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = 17*A008366(n).

%e a(2) = 17*17, a(3) = 17*19.

%t 17 * Select[Range[230], CoprimeQ[#, 30030] &] (* _Amiram Eldar_, Feb 24 2020 *)

%o (Rexx)

%o P = 17 ; S = P

%o do N = P by 2 while length( S ) < 255

%o do I = 1 until P = X

%o X = PRIME( I )

%o if P = X then leave I

%o if N // X = 0 then iterate N

%o end I

%o S = S || ',' P*N

%o end N

%o say S ; return S

%Y Cf. A084967 (5), A084968 (7), A084969 (11), A084970 (13), A332798 (19), A332797 (23), A008366 (17-rough numbers).

%K nonn,easy

%O 1,1

%A _Frank Ellermann_, Feb 24 2020