login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A189219 Zero-one sequence based on the octagonal numbers:  a(A000567(k))=a(k); a(A183220(k))=1-a(k), a(1)=0. 3

%I

%S 0,1,0,1,0,1,0,1,1,0,0,1,1,0,0,1,1,0,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,

%T 0,1,0,1,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,0,1,0,1,0,1,

%U 0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,1,0,1,0,1,0,0,1,0,1,0,1,1,0,1,0,1,0,0,1,0,1,0,1,1,0,1,0,1,0,0,1,0,1,0,1,0,1,0

%N Zero-one sequence based on the octagonal numbers: a(A000567(k))=a(k); a(A183220(k))=1-a(k), a(1)=0.

%t u[n_] := n(3n-2); (*A000567*)

%t a[1] = 0; h = 128;

%t c = (u[#1] &) /@ Range[2h];

%t d = (Complement[Range[Max[#1]], #1] &)[c]; (*A183220*)

%t Table[a[d[[n]]] = 1 - a[n], {n, 1, h - 1}]; (*A189219*)

%t Table[a[c[[n]]] = a[n], {n, 1, h}] (*A189219*)

%t Flatten[Position[%, 0]] (*A189220*)

%t Flatten[Position[%%, 1]] (*A189221*)

%Y Cf. A188967, A189220, A189221.

%K nonn

%O 1

%A _Clark Kimberling_, Apr 18 2011

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 16 17:04 EST 2019. Contains 329201 sequences. (Running on oeis4.)