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 A325507 #8 May 07 2019 23:14:32 %S A325507 1,2,6,28,340,3108,106932,2732340,236790060,19703562780,3419598096420, %T A325507 674127752953380,264134168649181380,95825592671995399620, %U A325507 67662122741507082338220,50556978553034312461203420,69259146896604886347745839660,104191622563656655781003976625020 %N A325507 Heinz number of the integer partition whose parts are the multiplicities in the multiset union of all integer partitions of n. %C A325507 Also the Heinz number of row n of A066633. %C A325507 The Heinz number of an integer partition or sequence (y_1,...,y_k) is prime(y_1)*...*prime(y_k). %H A325507 <a href="/index/He#Heinz">Index entries for sequences related to Heinz numbers</a> %F A325507 a(n) = Product_{i = 1..n} prime(A066633(n,i)). %F A325507 a(n) = A181819(A003963(A325500(n))). %F A325507 a(n) = A181819(A325501(n)). %F A325507 A001222(a(n)) = n. %F A325507 A056239(a(n)) = A006128(n). %F A325507 For n > 0, A181819(a(n)) = A087009(n + 1). %e A325507 The integer partitions of 4 are {(4), (3,1), (2,2), (2,1,1), (1,1,1,1)}, with multiset union {1,1,1,1,1,1,1,2,2,2,3,4}, with multiplicities (7,3,1,1), so a(4) = prime(7)*prime(3)*prime(1)*prime(1) = 340. %e A325507 The sequence of terms together with their prime indices begins: %e A325507 1: {} %e A325507 2: {1} %e A325507 6: {1,2} %e A325507 28: {1,1,4} %e A325507 340: {1,1,3,7} %e A325507 3108: {1,1,2,4,12} %e A325507 106932: {1,1,2,4,8,19} %e A325507 2732340: {1,1,2,3,6,11,30} %e A325507 236790060: {1,1,2,3,6,9,19,45} %e A325507 19703562780: {1,1,2,3,5,8,15,26,67} %e A325507 3419598096420: {1,1,2,3,5,8,13,21,41,97} %e A325507 674127752953380: {1,1,2,3,5,7,12,18,31,56,139} %e A325507 264134168649181380: {1,1,2,3,5,7,12,17,28,45,83,195} %e A325507 95825592671995399620: {1,1,2,3,5,7,11,16,25,38,63,112,272} %e A325507 67662122741507082338220: {1,1,2,3,5,7,11,16,24,35,55,87,160,373} %t A325507 Table[Times@@Prime/@Length/@Split[Sort[Join@@IntegerPartitions[n]]],{n,0,15}] %Y A325507 Cf. A001222, A003963, A006128, A007870, A056239, A066633, A087009, A112798, A215366, A302246, A325500, A325501, A325513. %K A325507 nonn %O A325507 0,2 %A A325507 _Gus Wiseman_, May 07 2019