A278063 Relative of Hofstadter Q-sequence: a(n) = n for 1 <= n <= 11; a(n) = a(n-a(n-1)) + a(n-a(n-2)) for n > 11.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 3, 12, 13, 5, 14, 6, 7, 15, 17, 10, 8, 17, 21, 12, 18, 14, 23, 11, 22, 26, 16, 13, 17, 15, 25, 11, 26, 35, 18, 23, 36, 24, 25, 27, 25, 25, 34, 26, 35, 26, 24, 25, 33, 30, 35, 22, 42, 17, 31, 47, 31, 30, 30

Offset

1,2

Comments

Similar to Hofstadter's Q-sequence A005185 but with different starting values.

This sequence has exactly 199 terms, since a(199)=206 and computing a(200) would refer to a(-6).

Links

Nathan Fox, Table of n, a(n) for n = 1..199

Nathan Fox, Hofstadter-like Sequences over Nonstandard Integers, Talk given at the Rutgers Experimental Mathematics Seminar, November 10 2016.

Mathematica

a[n_] := a[n] = If[0 < n < 12, n, a[n-a[n-1]] + a[n-a[n-2]]];
Array[a, 100] (* Paolo Xausa, May 30 2024 *)

Prog

(Magma) [n le 11 select n else Self(n-Self(n-1))+Self(n-Self(n-2)): n in [1..70]]; // Bruno Berselli, Nov 15 2016

Crossrefs

Cf. A005185, A278056, A278057, A278058, A278059, A278060, A278061, A278062, A278064, A278065.

Sequence in context: A297239 A043271 A333921 * A375931 A373231 A334684

Adjacent sequences: A278060 A278061 A278062 * A278064 A278065 A278066

Keyword

nonn,fini,full

Author

Nathan Fox, Nov 10 2016

Status

approved