factordbrpc · fdb
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Home prime · Base 21 of 781 length 21 Not fully computed yet - the last known term is composite. ↓ .elf file
Show sequence-development graph
Term size (digits) across the sequence
How the sequence develops - decimal digits of each term vs iteration.
nStatus DigitsTermFactorization
1 Fully factored 4 4922 2×23×107
2 Fully factored 6 399212 22×11×43×211
3 Fully factored 9 181858909 157×743×1559
4 Fully factored 11 13472163479<11> 61×389×567751
5 Fully factored 12 111455684041<12> 133×50730853
6 Fully factored 12 516277013152<12> 25×41×393503821
7 Fully factored 18 3243919880…12<18> 22×37×157×1439×3191×3040333
8 Fully factored 22 3003152543…01<22> 11×17×157243×495139×206270599
9 Fully factored 24 3559376884…69<24> 59×3897059×1548049998…49<16>
10 Fully factored 25 1801140702…87<25> 167×3671×3210953×914982602147<12>
11 Fully factored 27 1056072229…58<27> 2×11597×12517×3637623253…71<18>
12 Fully factored 30 2527050199…47<30> 153689×2687537×6118100861…79<18>
13 Fully factored 31 2036156918…85<31> 5×4409×408271×2262312569…63<21>
14 Fully factored 33 2963015421…48<33> 22×17×363683687×1198122372…53<23>
15 Fully factored 35 5092674043…41<35> 17×19×23×53087×2903503×175031947×254090094787<12>
16 Fully factored 39 1884385498…23<39> 4733611×2093867466…33<14>×1901200845…21<19>
17 Fully factored 40 5378670491…05<40> 5×13×4590771202…39<13>×1802502741…03<26>
18 Fully factored 42 5488739712…60<42> 23×5×193×1163×58321972393<11>×1048198220…17<25>
19 Fully factored 48 8359656601…57<48> 212909×303553×39468179×74346193913<11>×4408126602…83<19>
20 Composite 52 4035241091…57<52> 38959×1380389×27691467253<11>×2709656435…19<31>
↳ Open Open - the last known term is composite and not yet fully factored.
Open end - submit a factor of the remaining composite (31 digits) of term #20:
2709656435068802522297642798719
Check for factors - let the server run a small P-1 / P+1 / ECM step on the composite:
level 0 done · takes up to a minute
From the command linefdb · curl
fdb
fdb seq view '781' --type 38 --part last20
curl
curl -s 'https://factordb.com:4059/rpc' -H 'Content-Type: application/json' -d '{"jsonrpc":"2.0","id":1,"method":"sequence_view","params":{"start":{"expr":"781"},"type":38,"part":"last20","fr":0}}'