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A325506 Product of Heinz numbers over all strict integer partitions of n. 9

%I #7 May 07 2019 23:14:25

%S 1,2,3,30,70,2310,180180,21441420,6401795400,200984366583000,

%T 41615822944675980000,10515527757483671302380000,

%U 4919824049783476260137727416400000,5158181210492841550866520676965246284000000,29776760895364738730693151196801613158042403043600000000

%N Product of Heinz numbers over all strict integer partitions of n.

%C a(n) is the product of row n of A246867 (squarefree numbers arranged by sum of prime indices).

%C The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).

%F a(n) = Product_{i = 1..A000009(n)} A246867(n,i).

%F A001222(a(n)) = A015723(n).

%F A056239(a(n)) = A066189(n).

%F A003963(a(n)) = A325504(n).

%F a(n) = A003963(A325505(n)).

%e The strict integer partitions of 6 are {(6), (5,1), (4,2), (3,2,1)}, with Heinz numbers {13,22,21,30}, with product 13*22*21*30 = 180180, so a(6) = 180180.

%e The sequence of terms together with their prime indices begins:

%e 1: {}

%e 2: {1}

%e 3: {2}

%e 30: {1,2,3}

%e 70: {1,3,4}

%e 2310: {1,2,3,4,5}

%e 180180: {1,1,2,2,3,4,5,6}

%e 21441420: {1,1,2,2,3,4,4,5,6,7}

%e 6401795400: {1,1,1,2,2,3,3,4,5,5,6,7,8}

%e 200984366583000: {1,1,1,2,2,2,3,3,3,4,4,5,5,6,6,7,8,9}

%e 41615822944675980000: {1,1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,5,5,6,6,7,7,8,9,10}

%t Table[Times@@Prime/@(Join@@Select[IntegerPartitions[n],UnsameQ@@#&]),{n,0,15}]

%Y Cf. A003963, A006128, A015723, A022629, A056239, A112798, A147655, A215366, A246867, A325501, A325504, A325505, A325512, A325513.

%K nonn

%O 0,2

%A _Gus Wiseman_, May 07 2019

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Last modified April 19 19:02 EDT 2024. Contains 371798 sequences. (Running on oeis4.)