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A055358
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Number of increasing mobiles (circular rooted trees) with n nodes and 4 leaves.
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2
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6, 96, 874, 6040, 35458, 187288, 920350, 4297240, 19332662, 84615152, 362772194, 1531122296, 6385177274, 26382771464, 108232980822, 441554515704, 1793612585550, 7261158583200, 29318205685050
(list;
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refs;
listen;
history;
text;
internal format)
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OFFSET
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5,1
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LINKS
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FORMULA
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For n>0, a(n) = 31*2^(2*n - 3)/9 - 5*(n+2)*3^n/12 + (n^2 + 2*n + 2)*2^(n-2) - n^3/6 - n/4 - 1/18. - Vaclav Kotesovec, Mar 15 2022
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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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