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A334434 Heinz number of the n-th integer partition in graded lexicographic order.

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%I A334434 #20 Jan 26 2025 14:37:19
%S A334434 1,2,4,3,8,6,5,16,12,9,10,7,32,24,18,20,15,14,11,64,48,36,27,40,30,25,
%T A334434 28,21,22,13,128,96,72,54,80,60,45,50,56,42,35,44,33,26,17,256,192,
%U A334434 144,108,81,160,120,90,100,75,112,84,63,70,49,88,66,55,52,39,34,19
%N A334434 Heinz number of the n-th integer partition in graded lexicographic order.
%C A334434 A permutation of the positive integers.
%C A334434 This is the graded reverse of the so-called "Mathematica" order (A080577, A129129).
%C A334434 The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions.
%C A334434 As a triangle with row lengths A000041, the sequence starts {{1},{2},{4,3},{8,6,5},...}, so offset is 0.
%H A334434 Alois P. Heinz, <a href="/A334434/b334434.txt">Rows n = 0..28, flattened</a>
%H A334434 OEIS Wiki, <a href="http://oeis.org/wiki/Orderings of partitions">Orderings of partitions</a>
%H A334434 Wikiversity, <a href="https://en.wikiversity.org/wiki/Lexicographic_and_colexicographic_order">Lexicographic and colexicographic order</a>
%F A334434 A001222(a(n)) appears to be A049085(n).
%e A334434 The sequence of terms together with their prime indices begins:
%e A334434     1: {}              11: {5}                 45: {2,2,3}
%e A334434     2: {1}             64: {1,1,1,1,1,1}       50: {1,3,3}
%e A334434     4: {1,1}           48: {1,1,1,1,2}         56: {1,1,1,4}
%e A334434     3: {2}             36: {1,1,2,2}           42: {1,2,4}
%e A334434     8: {1,1,1}         27: {2,2,2}             35: {3,4}
%e A334434     6: {1,2}           40: {1,1,1,3}           44: {1,1,5}
%e A334434     5: {3}             30: {1,2,3}             33: {2,5}
%e A334434    16: {1,1,1,1}       25: {3,3}               26: {1,6}
%e A334434    12: {1,1,2}         28: {1,1,4}             17: {7}
%e A334434     9: {2,2}           21: {2,4}              256: {1,1,1,1,1,1,1,1}
%e A334434    10: {1,3}           22: {1,5}              192: {1,1,1,1,1,1,2}
%e A334434     7: {4}             13: {6}                144: {1,1,1,1,2,2}
%e A334434    32: {1,1,1,1,1}    128: {1,1,1,1,1,1,1}    108: {1,1,2,2,2}
%e A334434    24: {1,1,1,2}       96: {1,1,1,1,1,2}       81: {2,2,2,2}
%e A334434    18: {1,2,2}         72: {1,1,1,2,2}        160: {1,1,1,1,1,3}
%e A334434    20: {1,1,3}         54: {1,2,2,2}          120: {1,1,1,2,3}
%e A334434    15: {2,3}           80: {1,1,1,1,3}         90: {1,2,2,3}
%e A334434    14: {1,4}           60: {1,1,2,3}          100: {1,1,3,3}
%e A334434 Triangle begins:
%e A334434     1
%e A334434     2
%e A334434     4   3
%e A334434     8   6   5
%e A334434    16  12   9  10   7
%e A334434    32  24  18  20  15  14  11
%e A334434    64  48  36  27  40  30  25  28  21  22  13
%e A334434   128  96  72  54  80  60  45  50  56  42  35  44  33  26  17
%e A334434   ...
%e A334434 This corresponds to the tetrangle:
%e A334434                   0
%e A334434                  (1)
%e A334434                (11)(2)
%e A334434              (111)(21)(3)
%e A334434         (1111)(211)(22)(31)(4)
%e A334434   (11111)(2111)(221)(311)(32)(41)(5)
%p A334434 T:= n-> map(p-> mul(ithprime(i), i=p), combinat[partition](n))[]:
%p A334434 seq(T(n), n=0..8);  # _Alois P. Heinz_, Jan 26 2025
%t A334434 lexsort[f_,c_]:=OrderedQ[PadRight[{f,c}]];
%t A334434 Join@@Table[Times@@Prime/@#&/@Sort[IntegerPartitions[n],lexsort],{n,0,8}]
%t A334434 - or -
%t A334434 Join@@Table[Times@@Prime/@#&/@Reverse[IntegerPartitions[n]],{n,0,8}]
%Y A334434 Row lengths are A000041.
%Y A334434 The dual version (sum/revlex) is A129129.
%Y A334434 The constructive version is A193073.
%Y A334434 Compositions under the same order are A228351.
%Y A334434 The length-sensitive version is A334433.
%Y A334434 The version for reversed (weakly increasing) partitions is A334437.
%Y A334434 Lexicographically ordered reversed partitions are A026791.
%Y A334434 Reversed partitions in Abramowitz-Stegun order (sum/length/lex) are A036036.
%Y A334434 Reverse-lexicographically ordered partitions are A080577.
%Y A334434 Sorting reversed partitions by Heinz number gives A112798.
%Y A334434 Graded Heinz numbers are A215366.
%Y A334434 Sorting partitions by Heinz number gives A296150.
%Y A334434 Row sums give A145519.
%Y A334434 Cf. A036037, A049085, A056239, A066099, A185974, A211992, A228100, A228531, A333219, A334301, A334302, A334435, A334436, A334438, A334439.
%K A334434 nonn,look,tabf
%O A334434 0,2
%A A334434 _Gus Wiseman_, May 01 2020