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A274874 Number of set partitions of [n] into exactly ten blocks such that all odd elements are in blocks with an odd index and all even elements are in blocks with an even index. 2
1, 5, 95, 475, 5294, 26470, 227294, 1136470, 8351711, 41758555, 277114769, 1385573845, 8568214932, 42841074660, 251848578952, 1259242894760, 7132223195725, 35661115978625, 196428153720067, 982140768600335, 5296485323226634, 26482426616133170 (list; graph; refs; listen; history; text; internal format)
OFFSET

10,2

LINKS

Alois P. Heinz, Table of n, a(n) for n = 10..1000

FORMULA

G.f.: -x^10/((x-1)*(4*x+1)*(3*x-1)*(5*x-1)*(2*x+1)*(2*x-1)*(3*x+1)*(4*x-1)*(x+1)*(12*x^2-1)*(6*x^2-1)*(20*x^2-1)*(2*x^2-1)).

EXAMPLE

a(10) = 1: 1|2|3|4|5|6|7|8|9|(10).

a(11) = 5: 1(11)|2|3|4|5|6|7|8|9|(10), 1|2|3(11)|4|5|6|7|8|9|(10), 1|2|3|4|5(11)|6|7|8|9|(10), 1|2|3|4|5|6|7(11)|8|9|(10), 1|2|3|4|5|6|7|8|9(11)|(10).

CROSSREFS

Column k=10 of A274537.

Sequence in context: A116159 A054205 A116290 * A275292 A233077 A182960

Adjacent sequences:  A274871 A274872 A274873 * A274875 A274876 A274877

KEYWORD

nonn,easy

AUTHOR

Alois P. Heinz, Jul 09 2016

STATUS

approved

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Last modified August 8 21:55 EDT 2022. Contains 356016 sequences. (Running on oeis4.)