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A087720
Repeated terms in A005185.
0
1, 3, 5, 6, 8, 11, 12, 14, 16, 17, 23, 24, 30, 32, 43, 47, 48, 54, 60, 72, 80, 83, 84, 92, 94, 96, 148, 172, 175, 178, 185, 186, 192, 215, 222, 228, 230, 252, 273, 301, 308, 338, 350, 372, 380, 382, 384, 408, 468, 517, 574, 593, 624, 673, 678, 738, 748, 762, 764, 789
OFFSET
1,2
MATHEMATICA
digits=30000;
Hofstadter[n_Integer?Positive] := Hofstadter[n] = Hofstadter[n - Hofstadter[n-1]] + Hofstadter[n - Hofstadter[n-2]];
Hofstadter[1] = Hofstadter[2] = 1;
a1=Table[Hofstadter[n], {n, 1, digits}];
b=Table[If[a1[[n]]-a1[[n-1]]==0, a1[[n]], 0], {n, 2, digits}];
c=Delete[Union[b], 1]
CROSSREFS
Cf. A005185.
Sequence in context: A014254 A131422 A301744 * A309544 A154111 A047444
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Sep 29 2003
STATUS
approved