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%I #8 Dec 01 2012 17:02:04
%S 1,2,6,18,54,162,486,1458,4374,12866,37831,111961,331804,983200,
%T 2913064,8629984,25563928,75720112,224270920,664246912,1967449976,
%U 5827579985,17261274041,51127661518,151439081294,448558789858,1328619061294
%N Number of permutations of 1..n with i-8<=p(i)<=i+2.
%H R. H. Hardin, <a href="/A179349/b179349.txt">Table of n, a(n) for n = 1..400</a>
%F G.f.: -(1- x^2 - 2*x^3 - 4*x^4 - 8*x^5 - 14*x^6 - 24*x^7 - 34*x^8 - 12*x^9 - 56*x^10 + 11*x^11 + 16*x^12 + 19*x^13 + 12*x^14 + 28*x^15 + 8*x^17 + 16*x^18 + 4*x^19 + 20*x^20 - 5*x^22 - 8*x^23 - 3*x^24 - 10*x^25 - 2*x^28 - 2*x^30 + x^33 + x^35) / (-1 + x + 2*x^2 + 4*x^3 + 8*x^4 + 16*x^5 + 30*x^6 + 58*x^7 + 108*x^8 + 184*x^9 + 240*x^10 - 26*x^11 - 48*x^12 - 82*x^13 - 120*x^14 - 120*x^15 - 22*x^17 - 70*x^18 - 136*x^19 - 136*x^20 + 16*x^22 + 46*x^23 + 78*x^24 + 68*x^25 + 10*x^28 + 30*x^29 + 28*x^30 - 6*x^33 - 16*x^34 - 14*x^35 - 2*x^39 - 2*x^40 + x^44 + x^45). - _Vaclav Kotesovec_, Dec 01 2012
%K nonn
%O 1,2
%A _R. H. Hardin_, Jul 11 2010
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