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A120346
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Number of permutations avoiding 3142, 25314, 246135 and 362514.
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0
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1, 2, 6, 23, 102, 492, 2498, 13130, 70800, 389446, 2176802, 12328552, 70597568, 408061604, 2377643974, 13950607135, 82355028006, 488797440712, 2915087969496, 17459865132260, 104981190319396, 633438776314456
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OFFSET
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1,2
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COMMENTS
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These permutations are the wreath closure of 1, 12, 21 and 2413.
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LINKS
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FORMULA
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G.f. satisfies f^5+f^4+f^2+(x-1)f+x=0.
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EXAMPLE
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a(4)=23 because all permutations of length 4 except 3142 lies in this set.
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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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