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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A362621 One and numbers whose multiset of prime factors (with multiplicity) has the same median as maximum.

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%I A362621 #7 May 12 2023 09:13:45
%S A362621 1,2,3,4,5,7,8,9,11,13,16,17,18,19,23,25,27,29,31,32,37,41,43,47,49,
%T A362621 50,53,54,59,61,64,67,71,73,75,79,81,83,89,97,98,101,103,107,108,109,
%U A362621 113,121,125,127,128,131,137,139,147,149,151,157,162,163,167,169
%N A362621 One and numbers whose multiset of prime factors (with multiplicity) has the same median as maximum.
%C A362621 First differs from A334965 in having 750 and lacking 2250.
%C A362621 The median of a multiset is either the middle part (for odd length), or the average of the two middle parts (for even length).
%e A362621 The prime factorization of 108 is 2*2*3*3*3, and the multiset {2,2,3,3,3} has median 3 and maximum 3, so 108 is in the sequence.
%e A362621 The prime factorization of 2250 is 2*3*3*5*5*5, and the multiset {2,3,3,5,5,5} has median 4 and maximum 5, so 2250 is not in the sequence.
%e A362621 The terms together with their prime indices begin:
%e A362621      1: {}           25: {3,3}           64: {1,1,1,1,1,1}
%e A362621      2: {1}          27: {2,2,2}         67: {19}
%e A362621      3: {2}          29: {10}            71: {20}
%e A362621      4: {1,1}        31: {11}            73: {21}
%e A362621      5: {3}          32: {1,1,1,1,1}     75: {2,3,3}
%e A362621      7: {4}          37: {12}            79: {22}
%e A362621      8: {1,1,1}      41: {13}            81: {2,2,2,2}
%e A362621      9: {2,2}        43: {14}            83: {23}
%e A362621     11: {5}          47: {15}            89: {24}
%e A362621     13: {6}          49: {4,4}           97: {25}
%e A362621     16: {1,1,1,1}    50: {1,3,3}         98: {1,4,4}
%e A362621     17: {7}          53: {16}           101: {26}
%e A362621     18: {1,2,2}      54: {1,2,2,2}      103: {27}
%e A362621     19: {8}          59: {17}           107: {28}
%e A362621     23: {9}          61: {18}           108: {1,1,2,2,2}
%t A362621 Select[Range[100],(y=Flatten[Apply[ConstantArray,FactorInteger[#],{1}]];Max@@y==Median[y])&]
%Y A362621 Partitions of this type are counted by A053263.
%Y A362621 For mode instead of median we have A362619, counted by A171979.
%Y A362621 For parts at middle position (instead of median) we have A362622.
%Y A362621 The complement is A362980, counted by A237821.
%Y A362621 A027746 lists prime factors, A112798 indices, length A001222, sum A056239.
%Y A362621 A362611 counts modes in prime factorization, triangle version A362614.
%Y A362621 A362613 counts co-modes in prime factorization, triangle version A362615.
%Y A362621 Cf. A000040, A002865, A237824, A327473, A327476, A359908, A362616, A362620.
%K A362621 nonn
%O A362621 1,2
%A A362621 _Gus Wiseman_, May 12 2023