a(n) is the number from which if odd-positioned digits are deleted then one gets the concatenation of 1 to n, while if even-positioned digits are deleted then one gets reverse concatenation of 1 to n. Position of least significant digit is considered to be 1.
A078269
a(n) is the number from which if odd-positioned digits are deleted then one gets the concatenation of 1 to n, while if even-positioned digits are deleted then one gets reverse concatenation of 1 to n. Position of least significant digit is considered to be 1.
Terms
- a(0) =11a(1) =1221a(2) =132231a(3) =14233241a(4) =1524334251a(5) =162534435261
External references
- oeis: A078269