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A326646 Heinz numbers of non-constant integer partitions whose mean and geometric mean are both integers. 5
46, 57, 183, 194, 228, 371, 393, 454, 515, 687, 742, 838, 1057, 1064, 1077, 1150, 1157, 1159, 1244, 1322, 1563, 1895, 2018, 2060, 2116, 2157, 2163, 2167, 2177, 2225, 2231, 2405, 2489, 2854, 2859, 3249, 3263, 3339, 3352, 3558, 3669, 3758, 3787, 3914, 4265, 4351 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
The enumeration of these partitions by sum is given by A326642.
LINKS
Wikipedia, Geometric mean
EXAMPLE
The sequence of terms together with their prime indices begins:
46: {1,9}
57: {2,8}
183: {2,18}
194: {1,25}
228: {1,1,2,8}
371: {4,16}
393: {2,32}
454: {1,49}
515: {3,27}
687: {2,50}
742: {1,4,16}
838: {1,81}
1057: {4,36}
1064: {1,1,1,4,8}
1077: {2,72}
1150: {1,3,3,9}
1157: {6,24}
1159: {8,18}
1244: {1,1,64}
1322: {1,121}
CROSSREFS
Heinz numbers of partitions with integer mean and geometric mean are A326645.
Heinz numbers of partitions with integer mean are A316413.
Heinz numbers of partitions with integer geometric mean are A326623.
Non-constant partitions with integer mean and geometric mean are A326642.
Subsets with integer mean and geometric mean are A326643.
Strict partitions with integer mean and geometric mean are A326029.
Sequence in context: A115444 A119385 A330243 * A332952 A308099 A308252
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jul 16 2019
STATUS
approved

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Last modified April 24 19:59 EDT 2024. Contains 371963 sequences. (Running on oeis4.)