P · Proven prime
Enter a value, an expression, or a term with a variable like 10^n+1 to list a range.
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Term #1 of the aliquot sequence of
43929
Term #1 of the Home prime · Base 2 sequence of
5254
Term #1 of the Home prime · Base 6 sequence of
11278
Term #1 of the Home prime · Base 8 sequence of
8159
Term #1 of the Inverse home prime · Base 2 sequence of
15891
Term #1 of the Inverse home prime · Base 4 sequence of
15891
Term #2 of the Inverse home prime · Base 7 sequence of
629
Term #1 of the Home prime · Base 18 sequence of
4323
Term #1 of the Home prime · Base 22 sequence of
16297
Term #1 of the Home prime · Base 30 sequence of
11293
Term #1 of the Aliquot variants · Quasi · σ(n) − n − 1 sequence of
14088
Term #1 of the Inverse home prime · Base 21 sequence of
2018
Term #1 of the Inverse home prime · Base 22 sequence of
3655
Term #1 of the Conway climb · Base 2 sequence of
5254
Term #1 of the Conway climb · Base 6 sequence of
11278
Term #1 of the Conway climb · Base 8 sequence of
8159
Term #1 of the Conway climb · Base 16 sequence of
4975
Term #1 of the Conway climb · Base 18 sequence of
4323
Term #2 of the Conway climb · Base 21 sequence of
147
Term #1 of the Conway climb · Base 22 sequence of
16297
Term #1 of the Conway climb · Base 30 sequence of
11293
Term #1 of the Prime-stopping maps · σ(n) − 1 until a prime sequence of
15891
Term #1 of the Distinct-prime home prime · Base 2 sequence of
5254
Term #1 of the Distinct-prime home prime · Base 8 sequence of
8159
Term #1 of the Distinct-prime home prime, descending · Base 2 sequence of
15891
Term #1 of the Second-class home prime · Base 2 sequence of
10508
Term #1 of the Second-class home prime · Base 8 sequence of
16318
Term #2 of the Second-class home prime · Base 10 sequence of
3636
Term #1 of the Mid-divisor concatenation · Base 2 sequence of
16318
Term #2 of the Mid-divisor concatenation · Base 8 sequence of
7185
Term #1 of the Mid-divisor concatenation · Base 10 sequence of
4011
Term #1 of the Mid-divisor concatenation · Base 16 sequence of
16318
Is factor of
Primality
Verified directlyproven prime
Checked deterministically (below 300 digits).
From the command linefdb · curl
fdb
fdb number '21191' --detail 2
curl
curl -s 'https://factordb.com:4059/rpc' -H 'Content-Type: application/json' -d '{"jsonrpc":"2.0","id":1,"method":"get_number","params":{"target":{"expr":"21191"},"decimal":false,"detail":2}}'