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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See the expression syntax & functions reference.
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Term #1 of the Inverse home prime · Base 3 sequence of
13346
Term #1 of the Home prime · Base 12 sequence of
11143
Term #1 of the Home prime · Base 18 sequence of
5397
Term #1 of the Home prime · Base 20 sequence of
8042
Term #1 of the Home prime · Base 21 sequence of
2998
Term #1 of the Aliquot variants · Quasi · σ(n) − n − 1 sequence of
17898
Term #1 of the Inverse home prime · Base 23 sequence of
7733
Term #1 of the Inverse home prime · Base 29 sequence of
5819
Term #1 of the Conway climb · Base 6 sequence of
2682
Term #1 of the Conway climb · Base 12 sequence of
11143
Term #1 of the Conway climb · Base 18 sequence of
5397
Term #1 of the Conway climb · Base 20 sequence of
8042
Term #1 of the Conway climb · Base 21 sequence of
2998
Term #1 of the Prime-stopping maps · σ(n) − 1 until a prime sequence of
13346
Term #1 of the Distinct-prime home prime, descending · Base 3 sequence of
13346
Term #2 of the Second-class home prime · Base 16 sequence of
7064
Term #1 of the Mid-divisor concatenation · Base 2 sequence of
14548
Term #2 of the Mid-divisor concatenation · Base 3 sequence of
3687
Term #1 of the Mid-divisor concatenation · Base 8 sequence of
14548
Term #1 of the Mid-divisor concatenation · Base 16 sequence of
14548
Is factor of
Primality
Verified directlyproven prime
Checked deterministically (below 300 digits).
From the command linefdb · curl
fdb
fdb number '20021' --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":"20021"},"decimal":false,"detail":2}}'