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.
%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