a(0) = 1, a(1) = 0, a(2) = -1; for n >= 3, a(n) = - a(n-2) + Sum_{ primes p with 3 <= p <= n} a(n-p).
A002121
a(0) = 1, a(1) = 0, a(2) = -1; for n >= 3, a(n) = - a(n-2) + Sum_{ primes p with 3 <= p <= n} a(n-p).
Terms
- a(0) =1a(1) =0a(2) =-1a(3) =1a(4) =1a(5) =-1a(6) =0a(7) =2a(8) =0a(9) =-2a(10) =2a(11) =4a(12) =-3a(13) =-2a(14) =8a(15) =1a(16) =-8a(17) =8a(18) =12a(19) =-11a(20) =-4a(21) =25a(22) =4a(23) =-24a(24) =21a(25) =40a(26) =-31a(27) =-16a(28) =82a(29) =14
External references
- oeis: A002121