
COMMENTS

Up to n=9 the digits of a(n) sum up to n^2. Similar to this, A014824 (1,12,123,1234,...) is a representation of the triangular numbers; (1,1112,1112223,1112223334,...)of the pentagonal numbers;(1,11112,111122223,..) of the hexagonal numbers, and so on. A nice thing about this sequence(s) is that the (represented) value of the integer matches the partial sums of the number of digits in the sequence. a(n)=100*a(n1)+ A100706(n) gives a mirrored version of this sequence, and a(n)=10*a(n1)+ A100706(n) the symmetrical version (A002477).
