A151662 The first of three Hofstadter parents-child sequences of Thomas Stoll.

1, 0, 2, 1, 3, 3, 4, 4, 5, 7, 7, 8, 7, 10, 8, 10, 10, 11, 10, 13, 11, 13, 13, 14, 16, 16, 17, 16, 19, 17, 19, 19, 20, 21, 21, 22, 22, 23, 24, 24, 25, 24, 27, 25, 27, 27, 28, 30, 30, 31, 30, 33, 31, 33, 33, 34, 36, 36, 37, 36, 39, 37, 39, 39, 40, 39, 42, 40, 42, 42, 43, 45, 45, 46, 45, 48

Offset

0,3

Comments

Define three sequence a, b, c by: a[0]:=1; b[0]:=0; c[0]:=0; for n >= 1, b[n]:=n-c[b[n-1]]; a[n]:=n-b[a[n-1]]; c[n]:=n-a[c[n-1]].

Links

Hugo Pfoertner, Table of n, a(n) for n = 0..10000

Th. Stoll, On Hofstadter's married functions, Fib. Q., 46/47 (2008/2009), 62-67.

Maple

M:=130;
a[0]:=1; b[0]:=0; c[0]:=0;
for n from 1 to M do
b[n]:=n-c[b[n-1]];
a[n]:=n-b[a[n-1]];
c[n]:=n-a[c[n-1]];
od:
A:=[seq(a[n], n=0..M)];
B:=[seq(b[n], n=0..M)];
C:=[seq(c[n], n=0..M)];

Crossrefs

See also A151663, A151664. Cf. A005206, A005378, A005379.

Sequence in context: A360923 A123621 A370592 * A049786 A282611 A187498

Adjacent sequences: A151659 A151660 A151661 * A151663 A151664 A151665

Keyword

nonn

Author

N. J. A. Sloane, May 30 2009

Status

approved