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A373227
Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 7; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 7.
7
1, 2, 3, 4, 5, 6, 7, 6, 8, 9, 10, 9, 11, 12, 13, 12, 14, 15, 16, 15, 17, 18, 17, 20, 18, 20, 22, 21, 21, 22, 26, 25, 23, 24, 28, 26, 29, 26, 31, 30, 32, 28, 34, 30, 37, 29, 38, 35, 37, 33, 39, 40, 38, 37, 42, 43, 40, 40, 44, 42, 47, 43, 44, 46, 51, 46, 46, 50, 50, 50, 51, 53, 50
OFFSET
1,2
COMMENTS
Similar to A278055 but with different starting values.
Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.
a(n) exists for n <= 3*10^7.
MATHEMATICA
a[n_] := a[n] = If[0 < n < 8, n, a[n-a[n-1]] + a[n-a[n-2]] + a[n-a[n-3]]];
Array[a, 100] (* Paolo Xausa, May 31 2024 *)
CROSSREFS
Similar sequences based on the Q-recurrence: A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278063, A278064, A278065.
Sequence in context: A005599 A071934 A337642 * A331303 A161658 A066853
KEYWORD
nonn
AUTHOR
Nathan Fox, May 28 2024
STATUS
approved