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A087843
a(n) = a(n - a(n-1)) + a(a(a(n - a(n-2)))).
0
1, 1, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 7, 6, 7, 7, 7, 7, 7, 9, 7, 9, 8, 9, 9, 9, 9, 9, 11, 9, 11, 9, 11, 10, 11, 11, 11, 11, 11, 13, 11, 13, 11, 13, 11, 13, 12, 13, 13, 13, 13, 13, 16, 13, 15, 13, 16, 15, 15, 13, 16, 16, 15, 16, 16, 16, 16, 16, 19, 16, 18, 16, 19, 18, 19, 19, 18
OFFSET
1,3
COMMENTS
The fourth recursive of HofstadterQ second term of A005185.
MATHEMATICA
Hofstadter[n_Integer?Positive] := Hofstadter[n] = Hofstadter[n - Hofstadter[n-1]] + Hofstadter[Hofstadter[Hofstadter[n - Hofstadter[n-2]]]] Hofstadter[1] = Hofstadter[2] = 1 digits=200 a1=Table[Hofstadter[n], {n, 1, digits}]
CROSSREFS
Sequence in context: A130148 A341510 A196238 * A087831 A351960 A372759
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Oct 07 2003
STATUS
approved