A285696 Numbers such that the path described in Comments visits all digits once and ends in the position immediately after the last digit.
110, 11112, 33000, 110110, 313122, 1111114, 1133200, 1303102, 1333004, 1531202, 3103120, 3130210, 3300112, 3330014, 3333222, 3501122, 3531024, 5113220, 5310212, 5313024, 5500000, 5511222, 11011112, 11033000, 11112110, 11313142, 13030010, 15013020, 31312114
Offset: 1
Examples
For 33000 the digit positions visited are 1, 5, 4, 3, 2, 6(outside to the right) so 33000 is a term.
Links
- Lars Blomberg, Table of n, a(n) for n = 1..10000
Formula
Numbers must start with 1, 3, 5, 7, 9 and end with 0, 2, 4, 6, 8.
Let eSum = Sum_{i=1..k, d(i) is even} d(i)+1, and oSum = Sum_{i=1..k, d(i) is odd} d(i)+1. Then eSum-oSum+k = 0.
Comments