Number of points of self-intersection of the path of a billiard ball traveling at a 45-degree angle on a prime(n) X prime(n+1) billiard table. Also equal to 1/2 the number of the lattice points lying within a prime(n) X prime(n+1) rectangle.
A099407
Number of points of self-intersection of the path of a billiard ball traveling at a 45-degree angle on a prime(n) X prime(n+1) billiard table. Also equal to 1/2 the number of the lattice points lying within a prime(n) X prime(n+1) rectangle.
Terms
- a(0) =1a(1) =4a(2) =12a(3) =30a(4) =60a(5) =96a(6) =144a(7) =198a(8) =308a(9) =420a(10) =540a(11) =720a(12) =840a(13) =966a(14) =1196a(15) =1508a(16) =1740a(17) =1980a(18) =2310a(19) =2520a(20) =2808a(21) =3198a(22) =3608a(23) =4224a(24) =4800a(25) =5100a(26) =5406a(27) =5724a(28) =6048a(29) =7056
External references
- oeis: A099407