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A285696
Numbers such that the path described in Comments visits all digits once and ends in the position immediately after the last digit.
3
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
1,1
COMMENTS
Let d(1..k) be the digits in the number and let i = 1. If d(i) is odd set i = i+d(i)+1 else i = i-d(i)-1. The number is a term if i reaches k+1.
LINKS
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.
EXAMPLE
For 33000 the digit positions visited are 1, 5, 4, 3, 2, 6(outside to the right) so 33000 is a term.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Lars Blomberg and Eric Angelini, Apr 25 2017
STATUS
approved