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A275290 Number of set partitions of [n] with symmetric block size list of length five. 2
1, 3, 22, 86, 470, 2066, 10299, 47503, 229792, 1081851, 5189068, 24671320, 118223765, 565269659, 2713032552, 13022313334, 62644482305, 301600159952, 1454293747517, 7019496361595, 33922782653124, 164099194834163, 794642770006896, 3851565096708617 (list; graph; refs; listen; history; text; internal format)
OFFSET

5,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 5..500

Vaclav Kotesovec, Recurrence (of order 7)

Wikipedia, Partition of a set

FORMULA

a(n) ~ 5^n / (96*Pi*n). - Vaclav Kotesovec, Aug 02 2016

EXAMPLE

a(6) = 3: 1|2|34|5|6, 1|2|35|4|6, 1|2|36|4|5.

a(7) = 22: 12|3|4|5|67, 13|2|4|5|67, 1|23|4|56|7, 1|23|4|57|6, 14|2|3|5|67, 1|24|3|56|7, 1|24|3|57|6, 1|2|345|6|7, 1|2|346|5|7, 1|2|347|5|6, 15|2|3|4|67, 1|25|3|46|7, 1|25|3|47|6, 1|2|356|4|7, 1|2|357|4|6, 1|26|3|45|7, 1|27|3|45|6, 16|2|3|4|57, 1|26|3|47|5, 1|2|367|4|5, 1|27|3|46|5, 17|2|3|4|56.

CROSSREFS

Column k=5 of A275281.

Sequence in context: A106150 A135836 A004305 * A277228 A302272 A302723

Adjacent sequences:  A275287 A275288 A275289 * A275291 A275292 A275293

KEYWORD

nonn

AUTHOR

Alois P. Heinz, Jul 22 2016

STATUS

approved

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Last modified March 28 11:00 EDT 2020. Contains 333083 sequences. (Running on oeis4.)