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A321049
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Number of permutations of [n] with no fixed points where the maximal displacement of an element equals three.
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2
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0, 5, 18, 44, 116, 331, 932, 2532, 6720, 17804, 47280, 125460, 331736, 874973, 2305750, 6075184, 16001968, 42130767, 110885496, 291792264, 767776064, 2020061968, 5314529928, 13981117152, 36779372688, 96751538581, 254510051546, 669494097852, 1761102380100
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OFFSET
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3,2
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LINKS
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Index entries for linear recurrences with constant coefficients, signature (3,0,-3,6,-7,-11,-14,0,16,18,6,-7,1,-2,1,-2,-1,1).
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FORMULA
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G.f.: (x^10-x^9-2*x^8+3*x^7-x^6+2*x^5-7*x^4+x^3+10*x^2-3*x-5) * x^4 / ((x+1) *(x^4-2*x^3+x^2-2*x+1) *(x^13-x^11+x^10-x^9-x^8-9*x^7-3*x^6+3*x^5+7*x^4-x^3+x^2+2*x-1)).
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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