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A380470 Numbers k that are squarefree, but A380459(k) is not in A048103.

%I A380470 #15 May 09 2025 16:19:20
%S A380470 10,15,21,22,30,33,34,35,39,42,46,51,55,57,58,65,66,69,70,77,78,82,85,
%T A380470 87,91,93,94,95,102,105,106,110,111,114,115,118,119,123,129,130,133,
%U A380470 138,141,142,143,145,154,155,159,161,165,166,170,174,177,178,182,183,185,187,190,195,201,202,203,205,209,210,213
%N A380470 Numbers k that are squarefree, but A380459(k) is not in A048103.
%C A380470 See also comments in A380530.
%H A380470 Antti Karttunen, <a href="/A380470/b380470.txt">Table of n, a(n) for n = 1..20000</a>
%e A380470 From _Antti Karttunen_, May 09 2025: (Start)
%e A380470 10 = 2*5 is a term, as it is squarefree, and A380459(10) = 54 = 2 * 3^3, thus the prime factor 3 overflows, i.e., has an exponent at least as large as that prime.
%e A380470 5117046 = 2*3*11*31*41*61 is a term, as it is squarefree, and A380459(5117046) = 2 * 3^2 * 5^4 * 7^11 * 11^22 * 13^36 * 17^31 * 19^8, thus the least prime factor which overflows is 7 [= A380528(5117046)].
%e A380470 31203546 = 2*3*11*31*101*151 is a term, as it is squarefree, and A380459(31203546) = 2 * 3^2 * 5^4 * 7^6 * 11^28 * 13^37 * 17^56 * 19^18 * 23^2, thus the least prime factor which overflows is 11 [= A380528(31203546)].
%e A380470 (End)
%o A380470 (PARI) is_A380470 = A380469;
%Y A380470 Setwise difference A005117 \ A380468.
%Y A380470 Cf. A380469 (characteristic function), A380528, A380530.
%K A380470 nonn
%O A380470 1,1
%A A380470 _Antti Karttunen_, Feb 02 2025