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A123025 Let b(0) = 1, b(1) = 1; b(n+2) = -(n^2-n+1)*(b(n))/((n+2)*(n+1)). Then a(n) = n!*b(n). 0
1, 1, -1, -5, 11, 95, -319, -3895, 17545, 276545, -1561505, -30143405, 204557155, 4672227775, -37024845055, -976495604975, 8848937968145, 264630308948225, -2698926080284225, -90238935351344725, 1022892984427721275, 37810113912213439775, -471553665821179507775 (list; graph; refs; listen; history; internal format)
OFFSET

1,4

REFERENCES

Richard Bronson, Schaum's Outline of Modern Introductory Differential Equations, MacGraw-Hill, New York,1973, page 107, solved problem 19.17

MATHEMATICA

a[n_] := a[n] = -(n^2 - n - 1)*a[n - 2]/(n*(n - 1)); a[0] = 1; a[1] = 1; Table[a[n]*n!, {n, 0, 30}]

CROSSREFS

Sequence in context: A188514 A120778 A042761 * A053778 A030079 A066596

Adjacent sequences:  A123022 A123023 A123024 * A123026 A123027 A123028

KEYWORD

sign

AUTHOR

Roger Bagula (rlbagulatftn(AT)yahoo.com), Sep 24 2006

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com), Jan 06 2009

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Last modified February 17 16:27 EST 2012. Contains 206050 sequences.