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A334437 Heinz number of the n-th reversed integer partition in graded lexicographical order.

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%I A334437 #14 Sep 22 2023 08:56:41
%S A334437 1,2,4,3,8,6,5,16,12,10,9,7,32,24,20,18,14,15,11,64,48,40,36,28,30,22,
%T A334437 27,21,25,13,128,96,80,72,56,60,44,54,42,50,26,45,33,35,17,256,192,
%U A334437 160,144,112,120,88,108,84,100,52,90,66,70,34,81,63,75,39,55,49,19
%N A334437 Heinz number of the n-th reversed integer partition in graded lexicographical order.
%C A334437 A permutation of the positive integers.
%C A334437 Reversed integer partitions are finite weakly increasing sequences of positive integers. The non-reversed version is A334434.
%C A334437 This is the graded reverse of the so-called "Mathematica" order (A080577, A129129).
%C A334437 The Heinz number of a reversed integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and reversed partitions.
%C A334437 Also Heinz numbers of partitions in colexicographic order (cf. A211992).
%C A334437 As a triangle with row lengths A000041, the sequence starts {{1},{2},{4,3},{8,6,5},...}, so offset is 0.
%H A334437 Wikiversity, <a href="https://en.wikiversity.org/wiki/Lexicographic_and_colexicographic_order">Lexicographic and colexicographic order</a>
%F A334437 A001222(a(n)) = A193173(n).
%e A334437 The sequence of terms together with their prime indices begins:
%e A334437     1: {}              11: {5}                 44: {1,1,5}
%e A334437     2: {1}             64: {1,1,1,1,1,1}       54: {1,2,2,2}
%e A334437     4: {1,1}           48: {1,1,1,1,2}         42: {1,2,4}
%e A334437     3: {2}             40: {1,1,1,3}           50: {1,3,3}
%e A334437     8: {1,1,1}         36: {1,1,2,2}           26: {1,6}
%e A334437     6: {1,2}           28: {1,1,4}             45: {2,2,3}
%e A334437     5: {3}             30: {1,2,3}             33: {2,5}
%e A334437    16: {1,1,1,1}       22: {1,5}               35: {3,4}
%e A334437    12: {1,1,2}         27: {2,2,2}             17: {7}
%e A334437    10: {1,3}           21: {2,4}              256: {1,1,1,1,1,1,1,1}
%e A334437     9: {2,2}           25: {3,3}              192: {1,1,1,1,1,1,2}
%e A334437     7: {4}             13: {6}                160: {1,1,1,1,1,3}
%e A334437    32: {1,1,1,1,1}    128: {1,1,1,1,1,1,1}    144: {1,1,1,1,2,2}
%e A334437    24: {1,1,1,2}       96: {1,1,1,1,1,2}      112: {1,1,1,1,4}
%e A334437    20: {1,1,3}         80: {1,1,1,1,3}        120: {1,1,1,2,3}
%e A334437    18: {1,2,2}         72: {1,1,1,2,2}         88: {1,1,1,5}
%e A334437    14: {1,4}           56: {1,1,1,4}          108: {1,1,2,2,2}
%e A334437    15: {2,3}           60: {1,1,2,3}           84: {1,1,2,4}
%e A334437 Triangle begins:
%e A334437     1
%e A334437     2
%e A334437     4   3
%e A334437     8   6   5
%e A334437    16  12  10   9   7
%e A334437    32  24  20  18  14  15  11
%e A334437    64  48  40  36  28  30  22  27  21  25  13
%e A334437   128  96  80  72  56  60  44  54  42  50  26  45  33  35  17
%e A334437 This corresponds to the following tetrangle:
%e A334437                   0
%e A334437                  (1)
%e A334437                (11)(2)
%e A334437              (111)(12)(3)
%e A334437         (1111)(112)(13)(22)(4)
%e A334437   (11111)(1112)(113)(122)(14)(23)(5)
%t A334437 lexsort[f_,c_]:=OrderedQ[PadRight[{f,c}]];
%t A334437 Table[Times@@Prime/@#&/@Sort[Sort/@IntegerPartitions[n],lexsort],{n,0,8}]
%Y A334437 Row lengths are A000041.
%Y A334437 The constructive version is A026791 (triangle).
%Y A334437 The length-sensitive version is A185974.
%Y A334437 Compositions under the same order are A228351 (triangle).
%Y A334437 The version for non-reversed partitions is A334434.
%Y A334437 The dual version (sum/revlex) is A334436.
%Y A334437 Reversed partitions in Abramowitz-Stegun (sum/length/lex) order are A036036.
%Y A334437 Partitions in increasing-length colexicographic order (sum/length/colex) are A036037.
%Y A334437 Graded reverse-lexicographically ordered partitions are A080577.
%Y A334437 Sorting reversed partitions by Heinz number gives A112798.
%Y A334437 Graded lexicographically ordered partitions are A193073.
%Y A334437 Partitions in colexicographic order (sum/colex) are A211992.
%Y A334437 Graded Heinz numbers are given by A215366.
%Y A334437 Sorting partitions by Heinz number gives A296150.
%Y A334437 Partitions in dual Abramowitz-Stegun (sum/length/revlex) order are A334439.
%Y A334437 Cf. A056239, A066099, A129129, A228531, A333219, A333220, A334301, A334302, A334433, A334435, A334438.
%K A334437 nonn,tabf
%O A334437 0,2
%A A334437 _Gus Wiseman_, May 03 2020