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A370384
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Number of permutations of [n] having no substring [k,k+1,k+2,k+3,k+4,k+5].
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2
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1, 1, 2, 6, 24, 120, 719, 5037, 40306, 362802, 3628296, 39913080, 478970641, 6226733531, 87175347936, 1307641346772, 20922387099240, 355682119243320, 6402298503373917, 121643960874649867, 2432883613692550316, 51090627024035616300, 1123995015882951892680
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OFFSET
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0,3
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LINKS
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FORMULA
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G.f.: Sum_{k>=0} k! * ( (x-x^6)/(1-x^6) )^k.
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PROG
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(PARI) my(N=30, x='x+O('x^N)); Vec(sum(k=0, N, k!*((x-x^6)/(1-x^6))^k))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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