Number of arrangements of n+1 numbers x(i) in -2..2 with the sum of x(i)*x(i+1) equal to zero.
A188351
Number of arrangements of n+1 numbers x(i) in -2..2 with the sum of x(i)*x(i+1) equal to zero.
Terms
- a(0) =9a(1) =45a(2) =117a(3) =565a(4) =1953a(5) =9153a(6) =37269a(7) =173409a(8) =766869a(9) =3589357a(10) =16545861a(11) =78195505a(12) =368573829a(13) =1757922765a(14) =8394885777a(15) =40340645213a(16) =194259462205a(17) =938930726781
External references
- oeis: A188351