Number of permutations f of {1,...,prime(n)-1} with f(prime(n)-1) = prime(n)-1 and f(prime(n)-2) = prime(n)-2 such that 1/(f(1)*f(2)) + 1/(f(2)*f(3)) + ... + 1/(f(prime(n)-2)*f(prime(n)-1)) + 1/(f(prime(n)-1)*f(1)) == 0 (mod prime(n)^2).
A346387
Number of permutations f of {1,...,prime(n)-1} with f(prime(n)-1) = prime(n)-1 and f(prime(n)-2) = prime(n)-2 such that 1/(f(1)*f(2)) + 1/(f(2)*f(3)) + ... + 1/(f(prime(n)-2)*f(prime(n)-1)) + 1/(f(prime(n)-1)*f(1)) == 0 (mod prime(n)^2).
Terms
- a(0) =0a(1) =1a(2) =1a(3) =323a(4) =21615a(5) =301654585
External references
- oeis: A346387