OFFSET
0,5
COMMENTS
a(0)=0; a(n)= smallest nonnegative integer which is different from a(n-d)-a(k+d)-a(k) for every k=0..n-2 and d=1..n-k-1.
lim sup a(n)*log(n)*log(log(n))/n^2 seems to be positive and finite, maybe 1/pi.
Is the sequence surjective?
LINKS
Matthieu Pluntz, Table of n, a(n) for n = 0..2100
Matthieu Pluntz, MATLAB program
EXAMPLE
Determining a(4) : 0=a(3)+a(1)-a(0);1=a(3)+a(2)-a(1);2=a(2)+a(2)-a(0) are excluded, a(4)=3 is not.
CROSSREFS
KEYWORD
nonn
AUTHOR
Matthieu Pluntz, May 12 2014
STATUS
approved