|
Search: id:A056215
|
|
|
| A056215 |
|
Primes p for which the period of reciprocal = (p-1)/10. |
|
+0
4
|
|
| 281, 521, 1031, 1951, 2281, 2311, 2591, 3671, 5471, 5711, 6791, 7481, 8111, 8681, 8761, 9281, 9551, 10601, 11321, 12401, 13151, 13591, 14831, 14951, 15671, 16111, 16361, 18671, 21191, 21521, 21881, 24281, 24551, 25391, 25801, 25841, 26161
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Cyclic numbers of the tenth degree (or tenth order): the reciprocals of these numbers belong to one of ten different cycles. Each cycle has the (number minus 1)/10 digits.
|
|
LINKS
|
Index entries for sequences related to decimal expansion of 1/n
|
|
MATHEMATICA
|
f[n_Integer] := Block[{ds = Divisors[n - 1]}, (n - 1)/Take[ ds, Position[ PowerMod[ 10, ds, n], 1] [[1, 1]]] [[ -1]]]; Select[ Prime[ Range[4, 3000]], f[ # ] == 10 &]
|
|
CROSSREFS
|
Sequence in context: A139655 A161190 A098677 this_sequence A142397 A142546 A163184
Adjacent sequences: A056212 A056213 A056214 this_sequence A056216 A056217 A056218
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 15 2004
|
|
EXTENSIONS
|
Entry rfevised by N. J. A. Sloane (njas(AT)research.att.com), Apr 30 2007
|
|
|
Search completed in 0.002 seconds
|
