Carmichael numbers of the form (6*k+1)*(12*k+1)*(18*k+1) which are the product of four prime numbers.
A221742
Carmichael numbers of the form (6*k+1)*(12*k+1)*(18*k+1) which are the product of four prime numbers.
Terms
- a(0) =172081a(1) =1773289a(2) =4463641a(3) =295643089a(4) =798770161a(5) =1976295241a(6) =122160500281a(7) =374464040689a(8) =444722065201a(9) =676328168881
External references
- oeis: A221742