OFFSET
1,4
REFERENCES
D. Applegate and J. C. Lagarias, Distribution of 3x+1 trees, Experimental Mathematics 4 (1995),193-209.
LINKS
J. C. Lagarias, The 3x+1 problem and its generalizations, Amer. Math. Monthly, 92 (1985), 3-23.
Experimental Mathematics, Home Page
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved