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A276722
Number of set partitions of [n] such that for each block b the smallest integer interval containing b has at most six elements.
6
1, 1, 2, 5, 15, 52, 203, 674, 2066, 6184, 18587, 56867, 178317, 561319, 1760125, 5489888, 17057701, 52931331, 164466672, 511758485, 1593612234, 4962950389, 15451453190, 48088784307, 149640967002, 465653853729, 1449146745582, 4510183339086, 14037494547193
OFFSET
0,3
LINKS
FORMULA
G.f.: -(x^22 -x^19 -15*x^18 +7*x^17 +18*x^16 +11*x^14 -22*x^13 -26*x^12 -10*x^11 +2*x^10 -28*x^9 +3*x^8 +16*x^7 +14*x^6 -5*x^5 +5*x^4 +5*x^3 +2*x^2 -1) / (x^32 +5*x^31 +x^30 -5*x^29 -6*x^28 -111*x^27 -210*x^26 +52*x^25 +263*x^24 +85*x^23 -346*x^22 -882*x^21 -401*x^20 +584*x^19 +382*x^18 -1058*x^17 -1319*x^16 -200*x^15 +250*x^14 +382*x^13 +589*x^12 +716*x^11 +346*x^10 +49*x^9 -137*x^8 -146*x^7 -84*x^6 -3*x^5 -4*x^4 -5*x^3 -3*x^2 -x +1).
CROSSREFS
Column k=6 of A276719.
Sequence in context: A306551 A110038 A343666 * A287584 A287277 A287255
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Sep 16 2016
STATUS
approved