4*(107-1)/9 - 106 - 103 - 1
```Using Pari/gp (< 1s)
gp > isprime(4*(10^7-1)/9-10^6-10^3-1)
%1 = 1

```

4*(1011-1)/9 - 1010 - 105 - 1
```Using Pari/gp (< 1s)
gp > isprime(4*(10^11-1)/9-10^10-10^5-1)
%1 = 1

```

4*(1017-1)/9 - 1016 - 108 - 1
```Using Pari/gp (< 1s)
gp > isprime(4*(10^17-1)/9-10^16-10^8-1)
%1 = 1

```

4*(1047-1)/9 - 1046 - 1023 - 1
```Using Pari/gp (< 1s)
gp > isprime(4*(10^47-1)/9-10^46-10^23-1)
%1 = 1

```

4*(1055-1)/9 - 1054 - 1027 - 1
```Using Pari/gp (< 1s)
gp > isprime(4*(10^55-1)/9-10^54-10^27-1)
%1 = 1

```

4*(10367-1)/9 - 10366 - 10183 - 1
```Using Pari/gp (time = 2,234 ms)
gp > isprime(4*(10^367-1)/9-10^366-10^183-1)
%1 = 1

```

4*(10413-1)/9 - 10412 - 10206 - 1
```Using Pari/gp (time = 3,314 ms)
gp > isprime(4*(10^413-1)/9-10^412-10^206-1)
%1 = 1

```

4*(10955-1)/9 - 10954 - 10477 - 1
```Using Pari/gp (1min, 22,328 ms)
gp > default(parisizemax,"1G")
gp > isprime(4*(10^955-1)/9-10^954-10^477-1)
%1 = 1

```

4*(102641-1)/9 - 102640 - 101320 - 1
```Proven by certificate by Masaki UKAI (October 21, 2022)
http://factordb.com/index.php?id=1100000002732285048

```

4*(1025487-1)/9 - 1025486 - 1012743 - 1
```C:\pfgw>pfgw64 -q"4*(10^25487-1)/9-10^25486-10^12743-1"
PFGW Version 4.0.4.64BIT.20221214.Win_Dev [GWNUM 30.11]

4*(10^25487-1)/9-10^25486-10^12743-1 is 3-PRP! (3.2744s+0.0004s)

```

4*(1034489-1)/9 - 1034488 - 1017244 - 1
```C:\pfgw>pfgw64 -q"4*(10^34489-1)/9-10^34488-10^17244-1"
PFGW Version 4.0.4.64BIT.20221214.Win_Dev [GWNUM 30.11]

4*(10^34489-1)/9-10^34488-10^17244-1 is 3-PRP! (7.0442s+0.0008s)

```

```

```