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A068538 Nonsquarefree repunits. 0
111111111, 111111111111111111, 1111111111111111111111, 111111111111111111111111111, 111111111111111111111111111111111111, 111111111111111111111111111111111111111111 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The number of digits of these repunits form the sequence A046412. - Michel Marcus, Nov 24 2013

LINKS

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

PROG

(PARI) lista(nn) = {for (n=1, nn, if (! issquarefree(r = sum(i=0, n, 10^i)), print1(r, ", ")); ); } \\ Michel Marcus, Nov 24 2013

CROSSREFS

Sequence in context: A038451 A202082 A262499 * A186552 A147581 A281448

Adjacent sequences:  A068535 A068536 A068537 * A068539 A068540 A068541

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Mar 22 2002

STATUS

approved

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Last modified September 27 12:01 EDT 2020. Contains 337380 sequences. (Running on oeis4.)