Number of essentially different ways of arranging the numbers 1 through 2n around a circle so that the sum of each pair of adjacent numbers is semiprime.
A253202
Number of essentially different ways of arranging the numbers 1 through 2n around a circle so that the sum of each pair of adjacent numbers is semiprime.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =4a(4) =7a(5) =71a(6) =2555a(7) =24897a(8) =970556
External references
- oeis: A253202