|
| |
|
|
A180626
|
|
Numbers k such that 9*k! + 1 is prime.
|
|
9
|
|
|
|
2, 6, 7, 10, 13, 15, 24, 29, 33, 44, 98, 300, 548, 942, 1099, 1176, 1632, 1794, 3676, 3768, 4804
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,1
|
|
|
COMMENTS
|
Tested to 4500. - Robert G. Wilson v, Sep 28 2010
a(22) > 5235. - Jinyuan Wang, Feb 05 2020
|
|
|
LINKS
|
Table of n, a(n) for n=1..21.
Index entries for sequences related to numbers of primes of the form k*n!+-1
|
|
|
MATHEMATICA
|
fQ[n_] := PrimeQ[9 n! + 1]; k = 0; lst = {}; While[k < 1501, If[ fQ@k, AppendTo[lst, k]; Print@k]; k++ ]; lst
|
|
|
PROG
|
(PARI) is(k) = ispseudoprime(9*k!+1); \\ Jinyuan Wang, Feb 05 2020
|
|
|
CROSSREFS
|
Cf. A002981, A051915, A076679, A076680, A076681, A076682, A076683, A178488, A126896.
Sequence in context: A074223 A029459 A014862 * A061943 A029507 A047552
Adjacent sequences: A180623 A180624 A180625 * A180627 A180628 A180629
|
|
|
KEYWORD
|
nonn,more
|
|
|
AUTHOR
|
Robert G. Wilson v, Sep 13 2010
|
|
|
EXTENSIONS
|
a(17)-a(20) from Robert G. Wilson v, Sep 28 2010
a(21) from Jinyuan Wang, Feb 05 2020
|
|
|
STATUS
|
approved
|
| |
|
|
