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).

21, 1066338805156287287067, 1124161332414632881704, 2305867155177711644802, 2306166776784312535170, 5744341611556736174883

Offset

1,1

Links

Table of n, a(n) for n=1..6.

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

Adjacent sequences: A062009 A062010 A062011 * A062013 A062014 A062015

Keyword

base,fini,full,nice,nonn

Author

Erich Friedman, Jun 27 2001

Extensions

Name corrected by Michel Marcus, Dec 11 2017

Status

approved