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 A382301 #9 Mar 28 2025 22:54:32 %S A382301 1,1,2,2,3,6,8,9,14,16,25,30,41,52,69,83,105,129,164,208,263,315,388, %T A382301 449,573,694 %N A382301 Number of integer partitions of n having a unique multiset partition into constant blocks with distinct sums. %e A382301 The a(4) = 3 through a(8) = 14 partitions and their unique multiset partition into constant blocks with distinct sums: %e A382301 {4} {5} {6} {7} {8} %e A382301 {22} {1}{4} {33} {1}{6} {44} %e A382301 {1}{3} {2}{3} {1}{5} {2}{5} {1}{7} %e A382301 {11}{3} {2}{4} {3}{4} {2}{6} %e A382301 {1}{22} {11}{4} {11}{5} {3}{5} %e A382301 {2}{111} {11}{22} {1}{33} {11}{6} %e A382301 {1}{2}{3} {3}{22} {2}{33} %e A382301 {1}{11}{3} {1}{2}{4} {11}{33} %e A382301 {3}{1111} {11}{222} %e A382301 {1}{2}{5} %e A382301 {1}{3}{4} %e A382301 {1}{3}{22} %e A382301 {1}{4}{111} %e A382301 {1}{111}{22} %t A382301 hwt[n_]:=Total[Cases[FactorInteger[n],{p_,k_}:>PrimePi[p]*k]]; %t A382301 pfacs[n_]:=If[n<=1,{{}},Join@@Table[(Prepend[#,d]&)/@Select[pfacs[n/d],Min@@#>=d&],{d,Select[Rest[Divisors[n]],PrimePowerQ]}]]; %t A382301 Table[Length[Select[IntegerPartitions[n],Length[Select[pfacs[Times@@Prime/@#],UnsameQ@@hwt/@#&]]==1&]],{n,0,10}] %Y A382301 For distinct blocks instead of block-sums we have A000726, ranks A004709. %Y A382301 Twice-partitions of this type (constant with distinct) are counted by A279786. %Y A382301 MM-numbers of these multiset partitions are A326535 /\ A355743. %Y A382301 For no choices we have A381717, ranks A381636, zeros of A381635. %Y A382301 The Heinz numbers of these partitions are A381991, positions of 1 in A381635. %Y A382301 Normal multiset partitions of this type are counted by A382203. %Y A382301 For at least one choice we have A382427. %Y A382301 For strict instead of constant blocks we have A382460, ranks A381870. %Y A382301 A000041 counts integer partitions, strict A000009. %Y A382301 A000688 counts factorizations into prime powers, see A381455, A381453. %Y A382301 A001055 counts factorizations, strict A045778, see A317141, A300383, A265947. %Y A382301 A050361 counts factorizations into distinct prime powers. %Y A382301 Cf. A006171, A047966, A279784, A293511, A295935, A353864, A381633, A381716, A381990, A381992, A381993, A382079. %K A382301 nonn,more %O A382301 0,3 %A A382301 _Gus Wiseman_, Mar 26 2025