OFFSET
0,1
COMMENTS
An approximation to A001620.
A good lower bound for A001620 which maintains the ((10^k-1)/9/10^k)^(1/4) form is (111/1000)^(1/4) = 0.57720587746414... . - A.H.M. Smeets, Nov 15 2018
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
Dario Castellanos, The ubiquitous pi, Math. Mag., 61 (1988), 67-98 and 148-163.
EXAMPLE
.57735026774625008612242556400250089874160810195975716458187...
MATHEMATICA
RealDigits[(11111111 / 10^8)^(1/4), 10, 100][[1]] (* Vincenzo Librandi, Jul 24 2017 *)
PROG
(PARI) sqrtn(.11111111, 4) \\ Charles R Greathouse IV, Mar 25 2014
(Magma) SetDefaultRealField(RealField(100)); R:= RealField(); (11111111/10^8)^(1/4); // G. C. Greubel, Sep 04 2018
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
N. J. A. Sloane, Mar 24 2012
STATUS
approved