Integers are written in the form abcd...n where "a" means "At position a in this integer there is a digit b"; "b" means: "at position b there is a digit c"; "c" means: "at position c there is a digit d"; ... and "n" means nothing. No repetitions are allowed (like in the integer 111).

A105958

Integers are written in the form abcd...n where "a" means "At position a in this integer there is a digit b"; "b" means: "at position b there is a digit c"; "c" means: "at position c there is a digit d"; ... and "n" means nothing. No repetitions are allowed (like in the integer 111).