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A238857
Array read by rows: row n lists total number of m-digit right-truncatable reversible primes in base n.
8
0, 1, 1, 1, 0, 2, 1, 1, 0, 2, 4, 4, 2, 0, 3, 1, 1, 0, 3, 5, 3, 1, 0, 4, 7, 7, 5, 1, 0, 4, 5, 5, 3, 0, 4, 5, 6, 1, 0, 4, 8, 7, 9, 4, 1, 0, 5, 5, 7, 5, 0, 5, 10, 8, 4, 1, 1, 0, 6, 11, 17, 12, 3, 1, 0, 6, 11, 13, 6, 2, 1, 0, 6, 9, 11, 9, 4, 1, 0, 6, 13, 12, 7, 1, 0, 7, 9, 7, 1, 0
OFFSET
2,6
COMMENTS
For definitions and more comments, see A238854 and A238850.
This is an irregular table with one line for every base, starting at 2, while the columns correspond to the number of digits (1,2,3,...). Each row terminates with a zero (in any given base there appears to be a finite number of instances).
LINKS
Stanislav Sykora, PARI/GP scripts for genetic threads, with code and comments.
EXAMPLE
These are the first rows of the table:
2: 0,
3: 1, 1, 1, 0,
4: 2, 1, 1, 0,
5: 2, 4, 4, 2, 0,
6: 3, 1, 1, 0,
7: 3, 5, 3, 1, 0,
8: 4, 7, 7, 5, 1, 0,
9: 4, 5, 5, 3, 0,
10: 4, 5, 6, 1, 0,
...
Hence, there are 6 right truncatable reversible primes with 3 digits in base 10 (see A238850).
PROG
(PARI) See the link.
CROSSREFS
Full in base 10: A238850, 16: A238851, 100: A238852, 256: A238853.
In base n: A238854 (largest), A238855 (totals), A238856 (maximum digits).
Sequence in context: A227425 A333213 A301636 * A253587 A110962 A065715
KEYWORD
nonn,tabf,base
AUTHOR
Stanislav Sykora, Mar 13 2014
STATUS
approved