Number of permutations f of {1,...,n} with f(1) = 1 such that the n numbers prime(k) + prime(f(k)) + 1 (k = 1..n) are distinct primes.

A390695

Number of permutations f of {1,...,n} with f(1) = 1 such that the n numbers prime(k) + prime(f(k)) + 1 (k = 1..n) are distinct primes.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =0a(4) =2a(5) =2a(6) =0a(7) =4a(8) =20a(9) =88a(10) =18a(11) =0a(12) =224a(13) =0a(14) =0a(15) =1234a(16) =60428a(17) =5742a(18) =0a(19) =9276

External references