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Numbers with as many distinct even as distinct odd prime indices.
30

%I #5 May 17 2019 22:06:49

%S 1,6,12,14,15,18,24,26,28,33,35,36,38,45,48,51,52,54,56,58,65,69,72,

%T 74,75,76,77,86,93,95,96,98,99,104,106,108,112,116,119,122,123,135,

%U 141,142,143,144,145,148,152,153,158,161,162,172,175,177,178,185,192

%N Numbers with as many distinct even as distinct odd prime indices.

%C These are the Heinz numbers of the integer partitions counted by A241638.

%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.

%e The sequence of terms together with their prime indices begins:

%e 1: {}

%e 6: {1,2}

%e 12: {1,1,2}

%e 14: {1,4}

%e 15: {2,3}

%e 18: {1,2,2}

%e 24: {1,1,1,2}

%e 26: {1,6}

%e 28: {1,1,4}

%e 33: {2,5}

%e 35: {3,4}

%e 36: {1,1,2,2}

%e 38: {1,8}

%e 45: {2,2,3}

%e 48: {1,1,1,1,2}

%e 51: {2,7}

%e 52: {1,1,6}

%e 54: {1,2,2,2}

%e 56: {1,1,1,4}

%e 58: {1,10}

%t Select[Range[100],0==Total[(-1)^PrimePi/@First/@If[#==1,{},FactorInteger[#]]]&]

%Y A324967(n) = A324966(n).

%Y Cf. A001221, A026010, A028260, A045931, A063886, A097613, A112798, A130780, A239241, A241638, A325698, A325699.

%K nonn

%O 1,2

%A _Gus Wiseman_, May 17 2019