cp's OEIS Frontend

A324926 Numbers not divisible by any prime indices of their prime indices.

%I A324926 #10 Apr 14 2021 05:24:43
%S A324926 1,2,4,5,8,11,16,17,22,23,25,31,32,34,41,44,47,55,59,62,64,67,73,82,
%T A324926 83,85,88,97,103,109,115,118,121,124,125,127,128,134,137,149,157,164,
%U A324926 166,167,176,179,187,191,194,197,205,211,218,227,233,235,236,241,242
%N A324926 Numbers not divisible by any prime indices of their prime indices.
%C A324926 A prime index of n is a number m such that prime(m) divides n. For example, the prime indices of 55 are {3,5} with prime indices {{2},{3}}. Since 55 is not divisible by 2 or 3, it belongs to the sequence.
%H A324926 Amiram Eldar, <a href="/A324926/b324926.txt">Table of n, a(n) for n = 1..10000</a>
%e A324926 The sequence of multisets of multisets whose MM-numbers (see A302242) belong to the sequence begins:
%e A324926    1: {}
%e A324926    2: {{}}
%e A324926    4: {{},{}}
%e A324926    5: {{2}}
%e A324926    8: {{},{},{}}
%e A324926   11: {{3}}
%e A324926   16: {{},{},{},{}}
%e A324926   17: {{4}}
%e A324926   22: {{},{3}}
%e A324926   23: {{2,2}}
%e A324926   25: {{2},{2}}
%e A324926   31: {{5}}
%e A324926   32: {{},{},{},{},{}}
%e A324926   34: {{},{4}}
%e A324926   41: {{6}}
%e A324926   44: {{},{},{3}}
%e A324926   47: {{2,3}}
%e A324926   55: {{2},{3}}
%e A324926   59: {{7}}
%e A324926   62: {{},{5}}
%e A324926   64: {{},{},{},{},{},{}}
%t A324926 primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
%t A324926 Select[Range[100],And@@Table[!Divisible[#,i],{i,Union@@primeMS/@primeMS[#]}]&]
%Y A324926 Cf. A001222, A003963, A112798, A120383, A302242, A304360, A324846, A324847, A324848, A324849, A324850, A324927, A324928, A324930.
%K A324926 nonn
%O A324926 1,2
%A A324926 _Gus Wiseman_, Mar 21 2019