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%I #13 Apr 14 2021 03:13:06
%S 2,4,8,10,14,15,16,20,22,26,32,34,38,40,44,45,46,50,52,55,58,62,64,68,
%T 70,74,75,76,80,82,86,88,92,94,98,100,104,105,106,116,118,119,122,124,
%U 128,130,134,135,136,142,146,148,154,158,160,164,166,170,172,176
%N Numbers divisible by exactly one of their distinct prime indices.
%C Numbers n such that A324852(n) = 1.
%C A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
%H Amiram Eldar, <a href="/A323440/b323440.txt">Table of n, a(n) for n = 1..10000</a>
%e The sequence of terms together with their prime indices begins:
%e 2: {1}
%e 4: {1,1}
%e 8: {1,1,1}
%e 10: {1,3}
%e 14: {1,4}
%e 15: {2,3}
%e 16: {1,1,1,1}
%e 20: {1,1,3}
%e 22: {1,5}
%e 26: {1,6}
%e 32: {1,1,1,1,1}
%e 34: {1,7}
%e 38: {1,8}
%e 40: {1,1,1,3}
%e 44: {1,1,5}
%e 45: {2,2,3}
%e 46: {1,9}
%e 50: {1,3,3}
%e 52: {1,1,6}
%e 55: {3,5}
%t Select[Range[100],Count[If[#==1,{},FactorInteger[#]],{p_,_}/;Divisible[#,PrimePi[p]]]==1&]
%o (PARI) isok(n) = my(f=factor(n)[,1]); sum(k=1, #f, (n % primepi(f[k])) == 0) == 1; \\ _Michel Marcus_, Mar 22 2019
%Y Cf. A000720, A003963, A112798, A120383, A324704, A324846, A324847, A324848, A324849, A324850, A324856, A324926, A324929.
%K nonn
%O 1,1
%A _Gus Wiseman_, Mar 21 2019
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