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A246252
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Number of permutations of [n] with exactly seven occurrences of the consecutive step pattern up, down, down.
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2
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2172534146099019, 336291324862551606, 31816048233798681066, 2348418329934108057072, 149140942861163014893024, 8573289075750149662810032, 460018114299281721089786796, 23509721961960146267578379640, 1160583084129910496820714859320
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OFFSET
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22,1
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LINKS
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FORMULA
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a(n) ~ c * (3*sqrt(3)/(2*Pi))^n * n! * n^7, where c = 0.0000001405593242634352116... = c0 * (c0-1)^7 / (3^7 * 7!), and c0 = (1 + exp(Pi/sqrt(3))) * sqrt(3) / (2*Pi). - Vaclav Kotesovec, Aug 26 2014
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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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