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A062012
Decimal numbers k such that there is some base b such that (k regarded as a base-b number) = (1/b)*(k regarded as a base-10 number).
0
21, 1066338805156287287067, 1124161332414632881704, 2305867155177711644802, 2306166776784312535170, 5744341611556736174883
OFFSET
1,1
EXAMPLE
21_3 = 7 = 21/3, so 21 is a term.
30 is not a term because the base b would be 5 with 30_5 = 15, but 30 is not 5*15.
PROG
(PARI) isok(n) = {my (d = digits(n)); for (b=vecmax(d)+1, max(9, vecmax(d)-1), if (n == b*fromdigits(d, b), return (1)); ); return (0); } \\ Michel Marcus, Dec 11 2017
CROSSREFS
Subsequence of A062010.
Sequence in context: A013898 A180727 A250487 * A104786 A104787 A023922
KEYWORD
base,fini,full,nice,nonn
AUTHOR
Erich Friedman, Jun 27 2001
EXTENSIONS
Name corrected by Michel Marcus, Dec 11 2017
STATUS
approved