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A069575 Numbers n such that n contains the digit 0 in no base b with 2 < b < n. 4
4, 5, 7, 13, 23, 43, 157, 619 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Probably finite.

The next term (if it exists) is > 10000000. - Larry Reeves (larryr(AT)acm.org), Oct 12 2003

The next term (if it exists) is > 100000000. - Michel Marcus, Jul 14 2013

The next term (if it exists) is > 10^400. - Nathan Fox, Mar 09 2016

Every term in this sequence other than 4 is prime. - Nathan Fox, Mar 09 2016

No more terms through 10^5000. - Jon E. Schoenfield, Oct 13 2018

LINKS

Table of n, a(n) for n=1..8.

PROG

(PARI) isok(n) = {for (b=3, n-1, digs = digits(n, b); for (j=1, #digs, if (digs[j] == 0, return (0)); ); ); return (1); } \\ Michel Marcus, Jul 14 2013

CROSSREFS

Sequence in context: A139373 A293757 A275273 * A250182 A072215 A106170

Adjacent sequences:  A069572 A069573 A069574 * A069576 A069577 A069578

KEYWORD

base,nonn

AUTHOR

Naohiro Nomoto, Apr 18 2002

EXTENSIONS

Corrected by Larry Reeves (larryr(AT)acm.org), Oct 12 2003

STATUS

approved

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Last modified June 18 18:17 EDT 2021. Contains 345120 sequences. (Running on oeis4.)