factordb · sequences

Sequence

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whole sequence last 20 terms last term range to

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Inverse home prime · Base 15 of 25831 length 12 Not fully computed yet - the last known term is composite. ↓ .elf file

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Term size (digits) across the sequence — How the sequence develops - decimal digits of each term vs iteration.

n	Status	Digits	Term	Factorization
0	Fully factored	5	25831	13×1987
1	Fully factored	5	29818	2×17×877
2	Fully factored	7	2960132	2²×7×71×1489
3	Fully factored	10	1130950607<10>	8693×130099
4	Fully factored	10	6586270568<10>	2³×53×15533657
5	Fully factored	14	1179587096…32<14>	2²×31×95127991643<11>
6	Fully factored	16	4815854576…82<16>	2×1759×77893×17574343
7	Fully factored	18	6756167876…37<18>	11×6277×171161×57167711
8	Fully factored	20	3296578300…16<20>	2²×31×2658530887…09<18>
9	Fully factored	23	1345881261…32<23>	2²×17×53×8963×4166472963…41<15>
10	Fully factored	27	2402598261…82<27>	2×17×71×115597×1441049×597473408471<12>
11	Composite	31	3924449328…57<31>	3924449328…57<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 #11:

3924449328518008348347312961757

Check for factors - let the server run a small P-1 / P+1 / ECM step on the composite:

From the command linefdb · curl

fdb

fdb seq view '25831' --type 65 --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":"25831"},"type":65,"part":"last20","fr":0}}'