A278347 If n is even, a(n) = a(n/2 -1) - a(n/2 +1), and if n is odd, a(n) = a((n-1)/2) - a((n+1)/2), with a(1) = a(2) = 1.
1, 1, 0, 1, 1, 0, -1, -1, 0, 1, 1, 2, 1, 1, 0, -1, -1, -2, -1, -1, 0, -1, -1, 0, 1, 1, 0, 1, 1, 2, 1, 1, 0, 1, 1, 0, -1, -1, 0, -1, -1, 0, 1, 1, 0, -1, -1, -2, -1, -1, 0, 1, 1, 0, -1, -1, 0, -1, -1, 0, 1, 1, 0, 1, 1, 0, -1, -1, 0, 1, 1, 2, 1, 1, 0, -1, -1, 0, 1, 1, 0, -1, -1, -2, -1, -1, 0, 1, 1, 2, 1, 1, 0, 1, 1, 0, -1, -1, 0, -1, -1, -2, -1, -1, 0
Offset: 1
Links
- Tristan Cam and Robert G. Wilson v, Table of n, a(n) for n = 1..10000
Crossrefs
Cf. A277778.
Programs
-
Mathematica
a[n_] := a[n] = If[ OddQ[n], a[(n - 1)/2] - a[(n + 1)/2], a[n/2 - 1] - a[n/2 + 1]]; a[1] = a[2] = 1; Array[a, 105]
Formula
a(1) = 1 and a(2) = 1. a(n) = a(n/2 -1) - a(n/2 +1) if n is even and a(n) = a((n-1)/2) - a((n+1)/2) if n is odd.
Comments