A158912 - OEIS

A158912

Primitive numbers n whose square can be represented as a four "digit" repdigit number in some base < n.

20, 1218, 7540, 20280, 1373090, 4903600, 23308460, 316540365, 527813814, 4091661910, 16718044954, 1034412600, 142903074740, 1827252574658, 31036383127940

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OFFSET

1,1

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

20^2 = 1111 in base 7

1218^2 = (21)(21)(21)(21) in base 41

7540^2 = (58)(58)(58)(58) in base 99

CROSSREFS

A158235, A158245

Sequence in context: A184269 A042745 A363054 * A036067 A294191 A359645

Adjacent sequences: A158909 A158910 A158911 * A158913 A158914 A158915

KEYWORD

nonn,base

AUTHOR

T. D. Noe, Mar 30 2009

STATUS

approved