A089214 Let u(1)=0, u(2)=1; for k>2, u(k)= A010060(k)*u(k-1) + u(k-2) (mod 2); then a(n)=4n-b(n) where sequence (b(k)) gives values such that u(b(k))=0.

1, 3, 2, 4, 2, 4, 1, 3, 2, 4, 1, 3, 1, 3, 2, 4, 2, 4, 1, 3, 1, 3, 2, 4, 1, 3, 2, 4, 2, 4, 1, 3, 2, 4, 1, 3, 1, 3, 2, 4, 1, 3, 2, 4, 2, 4, 1, 3, 1, 3, 2, 4, 2, 4, 1, 3, 2, 4, 1, 3, 1, 3, 2, 4, 2, 4, 1, 3, 1, 3, 2, 4, 1, 3, 2, 4, 2, 4, 1, 3, 1, 3, 2, 4, 2, 4, 1, 3, 2, 4, 1, 3, 1, 3, 2, 4, 1, 3, 2, 4, 2, 4, 1, 3, 2

Offset

1,2

Comments

A word on 4 letters built from Thue-Morse sequence.

Links

Table of n, a(n) for n=1..105.

Prog

(PARI) u=0; v=1; c=0; for(n=3, 550, w=u%2+(subst(Pol(binary(n)), x, 1)%2)*v; u=v; v=w; if(w==0, c++; print1(4*c-n, ", ")))

Crossrefs

Sequence in context: A087023 A328052 A387078 * A057038 A175798 A294111

Adjacent sequences: A089211 A089212 A089213 * A089215 A089216 A089217

Keyword

nonn

Author

Benoit Cloitre, Dec 09 2003

Status

approved