

A004002


Benford numbers: a(n)=e^e^...^e (n times) rounded to nearest integer.
(Formerly M3010)


9




OFFSET

0,2


COMMENTS

The next term, a(4) ~ 2.3315*10^1656520, has 1656521 decimal digits and is therefore too large to be included. [Rephrased by M. F. Hasler, May 01 2013]
Named by Turner (1991) after the American electrical engineer and physicist Frank Albert Benford, Jr. (18831948).  Amiram Eldar, Jun 26 2021


REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).


LINKS

Table of n, a(n) for n=0..3.
C. W. Clenshaw, F. W. J. Olver and P. R. Turner, Levelindex arithmetic: An introductory survey in: P. R. Turner (ed.), Numerical Analysis and Parallel Processing, Lecture Notes in Mathematics, Vol. 1397, Springer, Berlin, Heidelberg, 1989, pp. 95168.
Peter R. Turner, Will the "real" real arithmetic please stand up?, Notices Amer. Math. Soc., Vol. 38 (1991), pp. 298304; entire issue.
Index entries for sequences related to Benford's law (The present sequence seems unrelated to Benford's law!)


FORMULA

a(n) = round(e^e^...^e), where e occurs n times, a(0) = 1 (= e^0).  Melissa O'Neill, Jul 04 2015


MATHEMATICA

Round[NestList[Power[E, #] &, 1, 3]] (* Melissa O'Neill, Jul 04 2015 *)


CROSSREFS

Cf. A056072, A225053.
Cf. A073236.  Melissa O'Neill, Jul 04 2015
Sequence in context: A202380 A290610 A134807 * A216149 A194604 A078355
Adjacent sequences: A003999 A004000 A004001 * A004003 A004004 A004005


KEYWORD

nonn


AUTHOR

N. J. A. Sloane


STATUS

approved



