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A284207
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Eleventh column of Euler's difference table in A068106.
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1
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0, 0, 0, 0, 0, 0, 0, 0, 0, 3628800, 36288000, 402796800, 4906137600, 64988179200, 929459059200, 14266826784000, 233845982899200, 4075249496774400, 75225258805132800, 1465957162768492800, 30071395843421184000, 647624841502298284800
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OFFSET
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1,10
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COMMENTS
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For n >= 11, this is the number of permutations of [n] that avoid substrings j(j+10), 1 <= j <= n-10.
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LINKS
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FORMULA
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For n>=11: a(n) = Sum_{j=0..n-10} (-1)^j*binomial(n-10,j)*(n-j)!.
Note a(n)/n! ~ 1/e.
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EXAMPLE
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a(14)=64988179200 since this is the number of permutations in S14 that avoid substrings {1(11),2(12),3(13),4(14)}.
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MATHEMATICA
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Table[Sum[(-1)^j*Binomial[n - 10, j]*(n - j)!, {j, 0, n - 10}], {n, 22}] (* Michael De Vlieger, Apr 03 2017 *)
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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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