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 A383513 #10 May 15 2025 08:23:23 %S A383513 6,12,18,21,24,30,36,42,48,54,60,63,65,66,70,72,78,84,90,96,102,105, %T A383513 108,110,114,120,126,132,133,138,140,144,147,150,154,156,162,165,168, %U A383513 174,180,186,189,192,198,204,210,216,220,222,228,231,234,238,240,246 %N A383513 Heinz numbers of non conjugate Wilf partitions. %C A383513 First differs from A381433 in having 65. %C A383513 The Heinz number of a partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). This gives a bijective correspondence between positive integers and integer partitions. %C A383513 An integer partition is Wilf iff its multiplicities are all different (ranked by A130091). It is conjugate Wilf iff its nonzero 0-appended differences are all different (ranked by A383512). %H A383513 Gus Wiseman, <a href="/A325325/a325325.txt">Sequences counting and ranking integer partitions by the differences of their successive parts.</a> %e A383513 The terms together with their prime indices begin: %e A383513 6: {1,2} %e A383513 12: {1,1,2} %e A383513 18: {1,2,2} %e A383513 21: {2,4} %e A383513 24: {1,1,1,2} %e A383513 30: {1,2,3} %e A383513 36: {1,1,2,2} %e A383513 42: {1,2,4} %e A383513 48: {1,1,1,1,2} %e A383513 54: {1,2,2,2} %e A383513 60: {1,1,2,3} %e A383513 63: {2,2,4} %e A383513 65: {3,6} %e A383513 66: {1,2,5} %e A383513 70: {1,3,4} %e A383513 72: {1,1,1,2,2} %e A383513 78: {1,2,6} %e A383513 84: {1,1,2,4} %e A383513 90: {1,2,2,3} %e A383513 96: {1,1,1,1,1,2} %t A383513 prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]]; %t A383513 Select[Range[100],!UnsameQ@@DeleteCases[Differences[Prepend[prix[#],0]],0]&] %Y A383513 Partitions of this type are counted by A336866. %Y A383513 The conjugate version is A130092, complement A130091. %Y A383513 Including differences of 0 gives complement of A325367, counted by A325324. %Y A383513 The strict case is the complement of A325388, counted by A320348. %Y A383513 The complement is A383512, counted by A098859. %Y A383513 Also forbidding distinct multiplicities gives A383531, counted by A383530. %Y A383513 These are positions of non-strict rows in A383534, or nonsquarefree numbers in A383535. %Y A383513 A000040 lists the primes, differences A001223. %Y A383513 A048767 is the Look-and-Say transform, union A351294, complement A351295. %Y A383513 A055396 gives least prime index, greatest A061395. %Y A383513 A056239 adds up prime indices, row sums of A112798, counted by A001222. %Y A383513 A122111 represents conjugation in terms of Heinz numbers. %Y A383513 A239455 counts Look-and-Say partitions, complement A351293. %Y A383513 A383507 counts partitions that are Wilf and conjugate Wilf, ranks A383532. %Y A383513 A383709 counts Wilf partitions with distinct augmented differences, ranks A383712. %Y A383513 Cf. A000720, A005117, A048768, A238745, A325325, A325351, A325355, A325366, A325368, A381431, A383506. %K A383513 nonn %O A383513 1,1 %A A383513 _Gus Wiseman_, May 13 2025