A206774 First differences of A033922.

0, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -4, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -4, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -4, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -6, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -4, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -1, 1, 0, 1, -4, 1, 0, 1, -1, 1, 0, 1, -1, 1

Offset: 1

Author

Benoit Cloitre, Jan 10 2013

Keywords

• sign
• base

Links

• Antti Karttunen, Table of n, a(n) for n = 1..16383

Crossrefs

Cf. A033922.

Programs

PARI

up_to = 16383;
A033922list(n) = { my(v, k, e); v=vector(n+1); v[1]=1; for(m=1, n, k=m; e=0; while(k>0, if(k%2, v[m+1]+=v[e+1]); e++; k\=2)); (v); }; \\ From A033922
v033922 = A033922list(16383);
A033922(n) = v033922[1+n];
A206774(n) = (A033922(n)-A033922(n-1)); \\ Antti Karttunen, Nov 06 2018

Formula

a(n) = A033922(n) - A033922(n-1).

For n >= 1, a(2n+1)=1, a(4n+2)=0, a(4*A042968(n))=-1, a(16*A042968(n))=-4, a(64*(2n+1))=-6. The values < 0 taken by the sequence are -1,-4,-6,-7, ... see A206775.

Extensions

More terms from Antti Karttunen, Nov 06 2018