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A346720
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a(n) is the number of negative Euler permutations of order 2*n. Bisection (even indices) of A347602.
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3
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0, 1, 2, 163, 6724, 692741, 86756038, 16135231015, 3838836369800, 1178853270354697, 447322130002332298, 206783054242756958891, 114117348385587556703692, 74183362210489714472590093, 56080450787901009525514063694, 48790757690364513377740990959151, 48400123863374755985614486072403728
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OFFSET
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0,3
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COMMENTS
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For definitions and comments see A347602.
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LINKS
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FORMULA
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a(n) = subfactorial(2*n) / 2 - Im(PolyLog(-2*n, i)).
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MAPLE
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MATHEMATICA
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A346720[n_] := Subfactorial[2 n]/2 - Im[PolyLog[-2 n, I]];
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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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