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A005168
n-th derivative of x^x at 1, divided by n.
(Formerly M0380)
4
1, 1, 1, 2, 2, 9, -6, 118, -568, 4716, -38160, 358126, -3662088, 41073096, -500013528, 6573808200, -92840971200, 1402148010528, -22554146644416, 385014881294496, -6952611764874240, 132427188835260480, -2653529921603890560, 55802195178451990896
OFFSET
1,4
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Alois P. Heinz, Table of n, a(n) for n = 1..400 (first 100 terms from T. D. Noe)
R. K. Guy, The strong law of small numbers. Amer. Math. Monthly 95 (1988), no. 8, 697-712.
R. K. Guy, The strong law of small numbers. Amer. Math. Monthly 95 (1988), no. 8, 697-712. [Annotated scanned copy]
R. R. Patterson and G. Suri, The derivatives of x^x, date unknown. Preprint. [Annotated scanned copy]
MAPLE
a:= n-> (n-1)! *coeftayl(x^x, x=1, n):
seq(a(n), n=1..30); # Alois P. Heinz, Aug 18 2012
MATHEMATICA
Rest[(NestList[ Factor[ D[ #1, x]] &, x^x, 23] /. (x -> 1))/Range[0, 23]] (* Robert G. Wilson v, Aug 10 2010 *)
PROG
(Python)
from sympy import var, diff
x = var('x')
y = x**x
l = [[y:=diff(y), y.subs(x, 1)/(n+1)][1] for n in range(10)]
print(l) # Nicholas Stefan Georgescu, Mar 02 2023
CROSSREFS
Cf. A005727.
Column k=2 of A295027 (for n>1), A295028.
Sequence in context: A073315 A298597 A066320 * A256591 A011149 A212990
KEYWORD
sign,easy,nice
EXTENSIONS
One more term from Robert G. Wilson v, Aug 10 2010
STATUS
approved