A180631 - OEIS

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A180631

Numbers k such that 10*k! - 1 is prime.

10

2, 3, 4, 33, 55, 95, 110, 148, 170, 612, 1155, 2295, 2473, 4143, 5671

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

a(16) > 12000. - Michael S. Branicky, Jul 04 2024

LINKS

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

Index entries for sequences related to numbers of primes of the form k*n!+-1

MATHEMATICA

fQ[n_] := PrimeQ[10 n! - 1]; k = 0; lst = {}; While[k < 1501, If[ fQ@k, AppendTo[lst, k]; Print@k]; k++ ]; lst

CROSSREFS

Cf. A002982, A076133, A076134, A099350, A099351, A180627, A180628, A180630, A180630.

Sequence in context: A028354 A028355 A074920 * A102842 A299169 A009263

Adjacent sequences: A180628 A180629 A180630 * A180632 A180633 A180634

KEYWORD

nonn,more

AUTHOR

Robert G. Wilson v, Sep 13 2010

EXTENSIONS

a(12)-a(14) from Jinyuan Wang, Feb 04 2020

a(15) from Michael S. Branicky, Jul 03 2024

STATUS

approved