OFFSET
0,1
EXAMPLE
Consider n=1103, the digit '0' is at 2nd position (looking from the right), digit '1' in 3rd and 4th place, digit '2' does not occur, digit '3' at 1st position, digits 4-9 do not occur. Thus a(1103) = 23401000000.
PROG
(PARI) a(n)={my(p=vector(10)); for(i=1, #n=if(n, Vecrev(digits(n)), [0]), p[n[i]+1]=if(p[n[i]+1], concat(p[n[i]+1], i), i)); p=concat(p); p[1]=Str(p[1]); eval(concat(p))}
CROSSREFS
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Jul 28 2015
STATUS
approved