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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.

A340597 Numbers with an alt-balanced factorization.

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%I A340597 #9 Jan 19 2021 09:44:54
%S A340597 4,12,18,27,32,48,64,72,80,96,108,120,128,144,160,180,192,200,240,256,
%T A340597 270,288,300,320,360,384,400,405,432,448,450,480,500,540,576,600,640,
%U A340597 648,672,675,720,750,768,800,864,896,900,960,972,1000,1008,1024,1080
%N A340597 Numbers with an alt-balanced factorization.
%C A340597 We define a factorization into factors > 1 to be alt-balanced if its length is equal to its greatest factor.
%e A340597 The sequence of terms together with their prime signatures begins:
%e A340597       4: (2)        180: (2,2,1)    450: (1,2,2)
%e A340597      12: (2,1)      192: (6,1)      480: (5,1,1)
%e A340597      18: (1,2)      200: (3,2)      500: (2,3)
%e A340597      27: (3)        240: (4,1,1)    540: (2,3,1)
%e A340597      32: (5)        256: (8)        576: (6,2)
%e A340597      48: (4,1)      270: (1,3,1)    600: (3,1,2)
%e A340597      64: (6)        288: (5,2)      640: (7,1)
%e A340597      72: (3,2)      300: (2,1,2)    648: (3,4)
%e A340597      80: (4,1)      320: (6,1)      672: (5,1,1)
%e A340597      96: (5,1)      360: (3,2,1)    675: (3,2)
%e A340597     108: (2,3)      384: (7,1)      720: (4,2,1)
%e A340597     120: (3,1,1)    400: (4,2)      750: (1,1,3)
%e A340597     128: (7)        405: (4,1)      768: (8,1)
%e A340597     144: (4,2)      432: (4,3)      800: (5,2)
%e A340597     160: (5,1)      448: (6,1)      864: (5,3)
%e A340597 For example, there are two alt-balanced factorizations of 480, namely (2*3*4*4*5) and (2*2*2*2*5*6), so 480 in the sequence.
%t A340597 facs[n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[facs[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]];
%t A340597 Select[Range[100],Select[facs[#],Length[#]==Max[#]&]!={}&]
%Y A340597 Numbers with a balanced factorization are A100959.
%Y A340597 These factorizations are counted by A340599.
%Y A340597 The twice-balanced version is A340657.
%Y A340597 A001055 counts factorizations.
%Y A340597 A045778 counts strict factorizations.
%Y A340597 A316439 counts factorizations by product and length.
%Y A340597 Other balance-related sequences:
%Y A340597 - A010054 counts balanced strict partitions.
%Y A340597 - A047993 counts balanced partitions.
%Y A340597 - A098124 counts balanced compositions.
%Y A340597 - A106529 lists Heinz numbers of balanced partitions.
%Y A340597 - A340596 counts co-balanced factorizations.
%Y A340597 - A340598 counts balanced set partitions.
%Y A340597 - A340600 counts unlabeled balanced multiset partitions.
%Y A340597 - A340653 counts balanced factorizations.
%Y A340597 - A340654 counts cross-balanced factorizations.
%Y A340597 - A340655 counts twice-balanced factorizations.
%Y A340597 Cf. A006141, A064174, A117409, A200750, A303975, A324518, A324522, A325134, A340607, A340608, A340611, A340656.
%K A340597 nonn
%O A340597 1,1
%A A340597 _Gus Wiseman_, Jan 15 2021