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A270173
Smallest number k such that A270172(k) = n.
2
0, 90, 80, 70, 60, 50, 40, 30, 20, 10, 100, 190, 180, 170, 160, 150, 140, 130, 120, 1010, 1200, 1290, 1280, 1270, 1260, 1250, 1240, 1230, 10120, 12010, 12300, 12390, 12380, 12370, 12360, 12350, 12340, 101230, 120120, 123010, 123400, 123490, 123480, 123470
OFFSET
0,2
PROG
(PARI) eva(n) = subst(Pol(n), x, 10)
increasedigits(n) = my(d=digits(n)); for(k=1, #d, d[k]++; if(d[k]==10, d[k]=0)); eva(d)
a270172(n) = my(x=n, i=0); while(#Str(x) > 1, x=increasedigits(x); i++); i
a(n) = my(k=0); while(a270172(k)!=n, k++); k
CROSSREFS
Sequence in context: A033410 A008901 A161823 * A003899 A271233 A050652
KEYWORD
nonn,base
AUTHOR
Felix Fröhlich, Mar 12 2016
STATUS
approved