

A106742


a[n] =a[a[a[a[a[n  a[n1]]]]]] + a[n  a[n2]].


2



1, 1, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 6, 7, 7, 7, 7, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 13
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OFFSET

1,3


COMMENTS

A sixthorder recursion based on Hofstadter's Qsequence A005185.
Different from A087839  see comments in that entry.
Different from A106733.


LINKS

Paolo P. Lava, Table of n, a(n) for n = 1..10000


MATHEMATICA

Hofstadter1[1] = Hofstadter1[2] = 1; Hofstadter1[n_Integer?Positive] := Hofstadter1[n] = Hofstadter1[Hofstadter1[Hofstadter1[Hofstadter1[Hofstadter1[n  Hofstadter1[n  1]]]]]] + Hofstadter1[ n  Hofstadter1[n  2]]; a = Table[Hofstadter1[n], {n, 1, digits}]


CROSSREFS

Cf. A087842, A005185, A087836, A004001, A087839, A106733.
Sequence in context: A130247 A209869 A087839 * A106733 A087838 A057627
Adjacent sequences: A106739 A106740 A106741 * A106743 A106744 A106745


KEYWORD

nonn


AUTHOR

Roger L. Bagula, May 30 2005


EXTENSIONS

Edited by N. J. A. Sloane, Jun 15 2007


STATUS

approved



