OFFSET
2,1
EXAMPLE
a(9)=1110 since 9 = 4*1 + 3*1 + 2*1 + 1*0 and alternatives such as 100000000 or 11000 are less efficient (while 211 is prohibited because the final digit is too big).
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Henry Bottomley, Jun 02 2000
STATUS
approved