OFFSET
0,3
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Rémy Sigrist, Table of n, a(n) for n = 0..10000
Joseph Gerver, James Propp and Jamie Simpson, Greedily partitioning the natural numbers into sets free of arithmetic progressions Proc. Amer. Math. Soc., Vol. 102, No. 3 (1988), 765-772.
James Propp and N. J. A. Sloane, Email, March 1994
FORMULA
a(n) = a([ 2n/3 ]) + a([ (2n+1)/3 ]).
PROG
(PARI) for (n=1, #a=vector(58), print1 (a[n]=if (n<=2, n-1, a[1+((2*n-2)\3)]+a[1+((2*n-1)\3)])", ")) \\ Rémy Sigrist, Jun 10 2021
CROSSREFS
KEYWORD
nonn,look
AUTHOR
EXTENSIONS
More terms from Rémy Sigrist, Jun 10 2021
STATUS
approved