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%I #10 Mar 21 2021 21:46:57
%S 7,9,14,18,19,21,23,25,27,28,36,38,42,46,49,50,53,54,56,57,63,72,76,
%T 81,84,92,97,98,100,103,106,108,112,114,115,121,125,126,131,133,144,
%U 147,152,159,162,168,171,184,189,194,196,200,206,212,216,224,227,228
%N Numbers whose product of prime indices is a nonprime prime power (A246547).
%C First differs from A320325 at a(43) = 152, A320325(43) = 151.
%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 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%e The sequence of all integer partitions whose Heinz numbers belong to the sequence begins: (4), (2,2), (4,1), (2,2,1), (8), (4,2), (9), (3,3), (2,2,2), (4,1,1), (2,2,1,1), (8,1), (4,2,1), (9,1), (4,4), (3,3,1), (16), (2,2,2,1), (4,1,1,1), (8,2), (4,2,2), (2,2,1,1,1), (8,1,1), (2,2,2,2), (4,2,1,1), (9,1,1), (25), (4,4,1), (3,3,1,1).
%t Select[Range[100],With[{x=Times@@Cases[FactorInteger[#],{p_,k_}:>PrimePi[p]^k]},!PrimeQ[x]&&PrimePowerQ[x]]&]
%Y Cf. A000720, A000961, A001597, A003963, A056239, A064573, A112798, A246547, A246655, A279787, A320322, A320325, A320698, A320700.
%K nonn
%O 1,1
%A _Gus Wiseman_, Oct 19 2018
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