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A121154 a(n) = the n-th divisor of r(n)^n, where r(n) = (10^n-1)/9 the repunits and the positive divisors of r(n)^n are written in order from smallest to largest. 0
1, 11, 9, 121, 11111, 13, 21613201, 1111, 333, 4961, 219660193449998401 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Sequence continues: n=12: unknown, n=13: 17530969, n=14: 562529, n=15: unknown, n=16: unknown, n=17: 79066065031254967758669825213076144489,

LINKS

Table of n, a(n) for n=1..11.

EXAMPLE

1, 11, 101, 121, 1111, 1331, 10201, 12221, 14641, 112211, 134431,... is the

beginning of the sequence of divisors of 1111^4 and 121 is the 4th term of

this sequence, so a(4) = 121.

CROSSREFS

Cf. A121067.

Sequence in context: A219746 A220664 A038323 * A256078 A078200 A105034

Adjacent sequences:  A121151 A121152 A121153 * A121155 A121156 A121157

KEYWORD

more,nonn

AUTHOR

Jason Earls, Aug 13 2006

STATUS

approved

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Last modified October 23 20:19 EDT 2018. Contains 316530 sequences. (Running on oeis4.)