Least k such that k*M(n)*M(n+4) + 1 is prime, where M(n) = A000668(n).

Terms

a(0) =20a(1) =18a(2) =4a(3) =22a(4) =112a(5) =28a(6) =28a(7) =52a(8) =28a(9) =616a(10) =1288a(11) =1342a(12) =9988a(13) =214a(14) =7666a(15) =3328a(16) =21658a(17) =18988a(18) =6868a(19) =22824a(20) =10746a(21) =3388a(22) =59256