login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A083286
Decimal expansion of K(3), a constant related to the Josephus problem.
12
1, 6, 2, 2, 2, 7, 0, 5, 0, 2, 8, 8, 4, 7, 6, 7, 3, 1, 5, 9, 5, 6, 9, 5, 0, 9, 8, 2, 8, 9, 9, 3, 2, 4, 1, 1, 3, 0, 6, 6, 1, 0, 5, 5, 6, 2, 3, 1, 3, 0, 3, 7, 4, 3, 2, 1, 8, 5, 4, 4, 3, 3, 8, 7, 3, 7, 8, 4, 3, 3, 9, 9, 9, 7, 2, 7, 4, 8, 4, 4, 7, 6, 3, 8, 3, 6, 1, 6, 5, 3, 9, 8, 3, 3, 2, 3, 3, 4, 1, 1, 0, 0
OFFSET
1,2
COMMENTS
The constant K(3) is related to the Josephus problem with q=3 and the computation of A054995.
The number also occurs in Washburn's solution cited in References. Regarding Washburn's limit more generally (with x in place of 3/2) results in a disconnected function as plotted by the Mathematica program below. - Clark Kimberling, Oct 24 2012
REFERENCES
Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 2.13, p. 131.
LINKS
A. M. Odlyzko and H. S. Wilf, Functional iteration and the Josephus problem, Glasgow Math. J. 33 (1991), 235-240.
A.H.M. Smeets, 100000 decimal digits.
E. T. H. Wang, Phillip C. Washburn, Problem E2604, American Mathematical Monthly, 84 (1977), 821-822.
Eric Weisstein's World of Mathematics, Power Ceilings.
EXAMPLE
1.62227050288476731595695...
MATHEMATICA
s[x_, 0] := 0; s[x_, n_] := Floor[x*s[x, n - 1]] + 1
c[x_, n_] := ((1/x)^n) s[x, n]
t = N[c[3/2, 800], 120]
RealDigits[t, 10] (* A083286 *)
(* Display of the surroundings of 3/2 *)
Plot[N[c[x, 20]], {x, 1, 3}]
(* Clark Kimberling, Oct 24 2012 *)
PROG
(PARI) p=1; N=10^4; for(n=1, N, p=ceil(3/2*p)); c=(p/(3/2)^N)+0.
(Python)
d, a, n, nmax = 3, 0, 0, 150000
while n < nmax:
n, a = n+1, (a*d)//(d-1)+1
nom, den, pos = a*(d-1)**n, d**n, 0
while pos < 20000:
dig, nom, pos = nom//den, (nom%den)*10, pos+1
print(pos, dig) # A.H.M. Smeets, Jul 05 2019
CROSSREFS
Sequence in context: A020795 A136710 A276801 * A247818 A325039 A172439
KEYWORD
nonn,cons,changed
AUTHOR
Ralf Stephan, Apr 23 2003
STATUS
approved