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A058692
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B(n) - 1, B(n) = Bell numbers, A000110.
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6
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1, 4, 14, 51, 202, 876, 4139, 21146, 115974, 678569, 4213596, 27644436, 190899321, 1382958544, 10480142146, 82864869803, 682076806158, 5832742205056, 51724158235371, 474869816156750, 4506715738447322, 44152005855084345
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OFFSET
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2,2
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LINKS
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Table of n, a(n) for n=2..23.
W. M. B. Dukes, Tables of matroids
W. M. B. Dukes, Counting and Probability in Matroid Theory, Ph.D. Thesis, Trinity College, Dublin, 2000.
W. M. B. Dukes, On the number of matroids on a finite set
Index entries for sequences related to matroids
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FORMULA
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G.f.: ( G(0) - 1 )/(1-x) where G(k) = 1 + (1-x)/(1-x*(k+2))/(1-x/(x+(1-x)/G(k+1) )); (recursively defined continued fraction). - Sergei N. Gladkovskii, Jan 21 2013
G.f.: 1/(x^3*(1-x)*G(0)) - 1/(1-x)/x^3 where G(k) = 1 - x/(x - 1/(1 + 1/(x*k-1)/G(k+1) )); (recursively defined continued fraction). - Sergei N. Gladkovskii, Feb 13 2013
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MAPLE
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a:=n->sum(stirling2(n, k), k=2..n): seq(a(n), n=2..23); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 28 2007
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MATHEMATICA
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f[n_] := Sum[ StirlingS2[n, k], {k, 2, n}]; Table[ f[n], {n, 2, 23}] - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Mar 29 2007
Table[BellB[n, 1] - 1, {n, 2, 23}] [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jul 16 2009]
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CROSSREFS
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A diagonal of A058710.
Sequence in context: A096241 A211303 A149488 * A165813 A198279 A211307
Adjacent sequences: A058689 A058690 A058691 * A058693 A058694 A058695
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KEYWORD
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nonn
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AUTHOR
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N. J. A. Sloane, Dec 30 2000
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STATUS
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approved
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