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 A366532 #5 Oct 16 2023 23:26:50 %S A366532 6,12,14,15,18,24,26,28,30,33,35,36,38,42,45,48,51,52,54,56,58,60,65, %T A366532 66,69,70,72,74,75,76,77,78,84,86,90,93,95,96,98,99,102,104,105,106, %U A366532 108,112,114,116,119,120,122,123,126,130,132,135,138,140,141,142 %N A366532 Heinz numbers of integer partitions with at least one even and odd part. %C A366532 These partitions are counted by A006477. %C A366532 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. %F A366532 Intersection of A324929 and A366322. %e A366532 The terms together with their prime indices begin: %e A366532 6: {1,2} %e A366532 12: {1,1,2} %e A366532 14: {1,4} %e A366532 15: {2,3} %e A366532 18: {1,2,2} %e A366532 24: {1,1,1,2} %e A366532 26: {1,6} %e A366532 28: {1,1,4} %e A366532 30: {1,2,3} %e A366532 33: {2,5} %e A366532 35: {3,4} %e A366532 36: {1,1,2,2} %e A366532 38: {1,8} %e A366532 42: {1,2,4} %e A366532 45: {2,2,3} %e A366532 48: {1,1,1,1,2} %t A366532 prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]]; %t A366532 Select[Range[100],Or@@EvenQ/@prix[#]&&Or@@OddQ/@prix[#]&] %Y A366532 These partitions are counted by A006477. %Y A366532 Just even: A324929, counted by A047967. %Y A366532 Just odd: A366322, counted by A086543 (even bisection of A182616). %Y A366532 A031368 lists primes of odd index, even A031215. %Y A366532 A066207 ranks partitions with all even parts, counted by A035363. %Y A366532 A066208 ranks partitions with all odd parts, counted by A000009. %Y A366532 A112798 lists prime indices, sum A056239. %Y A366532 A257991 counts odd prime indices, distinct A324966. %Y A366532 A257992 counts even prime indices, distinct A324967. %Y A366532 Cf. A000720, A001222, A003963, A026804, A244991, A257992. %K A366532 nonn %O A366532 1,1 %A A366532 _Gus Wiseman_, Oct 16 2023