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 A006572 Numerators of an asymptotic expansion for the number of forests on n nodes (A001858). (Formerly M3817) 3
 0, 0, 1, 5, 11, -203, -17207, -3607, 1408301, 8181503, -3299598169, -14983154641, -449428440959, 2480887997789, 19076621521399973, -31806561859970819, -3485566370059659659, -2180443004193000007, 54188073629843061671671 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Takacs Table 2 gives incorrect A006572(10)/A006573(10) = -137483257/61440 and A006572(11)/A006573(11) = -24971924401/983040. - Sean A. Irvine, May 11 2017 REFERENCES N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). L. Takacs, On the number of distinct forests, SIAM J. Discrete Math., 3 (1990), 574-581. LINKS FORMULA a(n) = numerator(Sum_{i=1..floor(n/2)} (-1)^(i-1) * |A111999(n, 2*i-1)| / (2^(n-i) * (n-i)!)). - Sean A. Irvine, May 11 2017 CROSSREFS Cf. A006573, A001858, A111999. Sequence in context: A179388 A229907 A181491 * A184934 A159009 A230841 Adjacent sequences:  A006569 A006570 A006571 * A006573 A006574 A006575 KEYWORD sign,frac AUTHOR EXTENSIONS a(10) and a(11) corrected and more terms from Sean A. Irvine, May 11 2017 STATUS approved

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Last modified January 23 10:59 EST 2019. Contains 319391 sequences. (Running on oeis4.)