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A354526 Numbers k such that A354512(k) < omega(k); complement of A354525. 4

%I #16 Aug 17 2022 05:07:26

%S 4,8,10,12,16,18,20,22,24,26,27,28,30,32,34,36,38,39,40,42,44,46,48,

%T 50,52,54,56,57,58,60,63,64,65,66,68,70,72,74,75,76,78,80,81,82,84,86,

%U 87,88,90,92,94,96,98,99,100,102,104,105,106,108,110,111,112,114,116,117

%N Numbers k such that A354512(k) < omega(k); complement of A354525.

%C Numbers k such that there is a prime factor p of k such that gpf(k+p) != p.

%C Numbers k such that there is a prime factor p of k such that k+p is not p-smooth.

%H Jianing Song, <a href="/A354526/b354526.txt">Table of n, a(n) for n = 1..7946</a> (all terms <= 10000)

%e 57 is a term since the prime factors of 57 are 3,19, and we have gpf(57+3) != 3.

%o (PARI) gpf(n) = vecmax(factor(n)[, 1]);

%o isA354526(n) = my(f=factor(n)[, 1]); for(i=1, #f, if(gpf(n+f[i])!=f[i], return(1))); 0

%Y Cf. A001221, A354512, A006530. Indices of positive terms in A354527.

%K nonn,easy

%O 1,1

%A _Jianing Song_, Aug 16 2022

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Last modified May 21 00:58 EDT 2024. Contains 372720 sequences. (Running on oeis4.)