a(1) = 5, a(n) = concatenation of two closest factors of a(n-1) whose product equals a(n-1) or if a(n-1) is a prime then the concatenation of 1 and a(n-1).
A063382
a(1) = 5, a(n) = concatenation of two closest factors of a(n-1) whose product equals a(n-1) or if a(n-1) is a prime then the concatenation of 1 and a(n-1).
Terms
- a(0) =5a(1) =15a(2) =35a(3) =57a(4) =319a(5) =1129a(6) =11129a(7) =31359a(8) =310453a(9) =1691837a(10) =7241691a(11) =15094799a(12) =31486929a(13) =159198031a(14) =1159198031a(15) =6203186877a(16) =11721529237a(17) =88429132553a(18) =129487682919
External references
- oeis: A063382