A067935 Let rep(n) be the n-th repunit number, sequence gives values of n such that : rep(n)==rep(2) (mod n).

1, 2, 4, 5, 10, 14, 20, 22, 25, 26, 34, 38, 44, 46, 50, 58, 62, 74, 82, 86, 94, 100, 106, 110, 118, 122, 134, 140, 142, 146, 158, 166, 178, 182, 185, 194, 202, 206, 214, 218, 220, 226, 254, 260, 262, 274, 278, 298, 302, 308, 314, 326, 334, 346, 350, 358, 362

Offset

1,2

Comments

(10^5-1)/9 = 11+5*2220, hence 5 is in the sequence.

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Maple

filter:= n -> 10&^n -100 mod (9*n) = 0:
select(filter, [$1..400]); # Robert Israel, Jul 02 2019

Crossrefs

Cf. A002275, A095250 (rep(n) mod n).

Sequence in context: A008283 A002237 A329136 * A228893 A272622 A097133

Adjacent sequences: A067932 A067933 A067934 * A067936 A067937 A067938

Keyword

nonn

Author

Benoit Cloitre, Mar 05 2002

Status

approved