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A325234 Heinz numbers of integer partitions with Dyson rank -1.

%I A325234 #6 Apr 13 2019 22:16:52
%S A325234 4,12,18,27,40,60,90,100,112,135,150,168,225,250,252,280,352,375,378,
%T A325234 392,420,528,567,588,625,630,700,792,832,880,882,945,980,1050,1188,
%U A325234 1232,1248,1320,1323,1372,1470,1575,1750,1782,1848,1872,1936,1980,2058,2080
%N A325234 Heinz numbers of integer partitions with Dyson rank -1.
%C A325234 Numbers whose maximum prime index is one fewer than their number of prime indices counted with multiplicity.
%C A325234 The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
%H A325234 FindStat, <a href="http://www.findstat.org/StatisticsDatabase/St000145">St000145: The Dyson rank of a partition</a>
%e A325234 The sequence of terms together with their prime indices begins:
%e A325234      4: {1,1}
%e A325234     12: {1,1,2}
%e A325234     18: {1,2,2}
%e A325234     27: {2,2,2}
%e A325234     40: {1,1,1,3}
%e A325234     60: {1,1,2,3}
%e A325234     90: {1,2,2,3}
%e A325234    100: {1,1,3,3}
%e A325234    112: {1,1,1,1,4}
%e A325234    135: {2,2,2,3}
%e A325234    150: {1,2,3,3}
%e A325234    168: {1,1,1,2,4}
%e A325234    225: {2,2,3,3}
%e A325234    250: {1,3,3,3}
%e A325234    252: {1,1,2,2,4}
%e A325234    280: {1,1,1,3,4}
%e A325234    352: {1,1,1,1,1,5}
%e A325234    375: {2,3,3,3}
%e A325234    378: {1,2,2,2,4}
%e A325234    392: {1,1,1,4,4}
%t A325234 Select[Range[1000],PrimePi[FactorInteger[#][[-1,1]]]-PrimeOmega[#]==-1&]
%Y A325234 Positions of -1's in A257541.
%Y A325234 Cf. A001222, A047993, A056239, A061395, A063995, A101198, A106529, A112798, A257990, A263297, A325225, A325233, A325235.
%K A325234 nonn
%O A325234 1,1
%A A325234 _Gus Wiseman_, Apr 13 2019