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A087814 Sequence gives A087655(n) for those n such that A087655(n) = A087655(n+1). 0
1, 1, 13, 15, 25, 39, 47, 51, 69, 81, 101, 139, 249, 261, 275, 291, 739, 1243, 2243 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..18.

MATHEMATICA

Hofstadter123[n_Integer?Positive] := Hofstadter123[n] = Hofstadter123[Abs[n - Hofstadter123[n-1]]] + Hofstadter123[Abs[n - Hofstadter123[n-2]]]+ Hofstadter123[Abs[n - Hofstadter123[n-3]]] Hofstadter123[0] =Hofstadter123[1] = Hofstadter123[2]= Hofstadter123[3]= 1 digits=30000 ta=Table[Hofstadter123[n], {n, 1, digits}]; b=Table[If[ta[[n]]-ta[[n-1]]==0, ta[[n]], 0], {n, 2, digits}]; c=Delete[Union[b], 1]

CROSSREFS

Cf. A087655.

Sequence in context: A140646 A109656 A178724 * A227449 A113801 A108257

Adjacent sequences:  A087811 A087812 A087813 * A087815 A087816 A087817

KEYWORD

nonn

AUTHOR

Roger L. Bagula, Oct 05 2003

STATUS

approved

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Last modified October 17 10:50 EDT 2017. Contains 293469 sequences.