If n is not composite, a(n) = n followed by 1; if n is composite, a(n) = concatenation of prime factors of n.
A049201
If n is not composite, a(n) = n followed by 1; if n is composite, a(n) = concatenation of prime factors of n.
Terms
- a(0) =1a(1) =11a(2) =21a(3) =31a(4) =22a(5) =51a(6) =23a(7) =71a(8) =222a(9) =33a(10) =25a(11) =111a(12) =223a(13) =131a(14) =27a(15) =35a(16) =2222a(17) =171a(18) =233a(19) =191a(20) =225a(21) =37a(22) =211a(23) =231a(24) =2223a(25) =55a(26) =213a(27) =333a(28) =227a(29) =291
External references
- oeis: A049201