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A087827
a(n) = a(a(Min(n-1,Abs(n-a(n-1)))))+a(Abs(n-a(n-3))).
0
1, 1, 1, 2, 3, 4, 4, 4, 4, 6, 5, 6, 6, 6, 6, 10, 7, 9, 8, 10, 9, 10, 10, 10, 10, 16, 10, 13, 12, 14, 13, 14, 12, 15, 15, 14, 16, 16, 16, 16, 16, 26, 14, 19, 18, 20, 19, 20, 18, 19, 19, 21, 21, 21, 21, 21, 20, 26, 22, 26, 21, 26, 26, 24, 26, 26, 24, 34, 20, 28, 22, 29, 26, 31, 28, 29
OFFSET
0,4
COMMENTS
A triple recursion of the skip one Hofstadter Q.
MATHEMATICA
Hofstadter3[n_Integer?Positive] := Hofstadter3[n] = Hofstadter3[Hofstadter3[Min[n-1, Abs[n - Hofstadter3[n-1]]]]] + Hofstadter3[Abs[n - Hofstadter3[n-3]]]
Hofstadter3[0]=Hofstadter3[1] = Hofstadter3[2]= Hofstadter3[3]= 1
digits=200
ta=Table[Hofstadter3[n], {n, 1, digits}]
CROSSREFS
Cf. A005185.
Sequence in context: A195849 A376571 A372450 * A136528 A263252 A276334
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Oct 06 2003
STATUS
approved