A206774 - OEIS

%I #16 Feb 16 2021 05:46:00

%S 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,

%T -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,

%U 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

%N First differences of A033922.

%H Antti Karttunen, <a href="/A206774/b206774.txt">Table of n, a(n) for n = 1..16383</a>

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

%F 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.

%o (PARI)

%o up_to = 16383;

%o 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

%o v033922 = A033922list(16383);

%o A033922(n) = v033922[1+n];

%o A206774(n) = (A033922(n)-A033922(n-1)); \\ _Antti Karttunen_, Nov 06 2018

%Y Cf. A033922.

%K sign,base

%O 1,16

%A _Benoit Cloitre_, Jan 10 2013

%E More terms from _Antti Karttunen_, Nov 06 2018