a(n) is the smallest product of prime numbers such that all numbers from 6 and 2n can be written as the sum of two prime factors (duplication allowed) of a(n).
A237628
a(n) is the smallest product of prime numbers such that all numbers from 6 and 2n can be written as the sum of two prime factors (duplication allowed) of a(n).
Terms
- a(0) =3a(1) =15a(2) =15a(3) =105a(4) =105a(5) =1155a(6) =1155a(7) =1365a(8) =15015a(9) =15015a(10) =15015a(11) =255255a(12) =255255a(13) =596505a(14) =4849845a(15) =4849845a(16) =4849845a(17) =10140585a(18) =10140585a(19) =179444265a(20) =229474245a(21) =229474245a(22) =242777535a(23) =640049865a(24) =5898837945a(25) =7357214865a(26) =7357214865a(27) =7357214865a(28) =13350001665a(29) =196656364905
External references
- oeis: A237628