A261408 Numbers k such that A260864(k) is a prime or probable prime, where A260864(k) is the number whose base-14 representation is the concatenation of the base-14 representations of (1, ..., k, k-1, ..., 1).

21, 34, 192, 310, 373, 536, 12000

Offset: 1

Author

N. J. A. Sloane, Aug 22 2015

Keywords

• nonn
• more

Comments

The subsequence of those A261171(n) for which A261172(n) = 14. - M. F. Hasler, Aug 23 2015

References

• David Broadhurst, email to N. J. A. Sloane, Aug 23 2015

Crossrefs

Cf. A260343, A260864.

See also A260871 which lists all primes of the form A[b](k), and A261171 and A261172 which list the k and b values of these primes. - M. F. Hasler, Aug 23 2015

Extensions

More explicit title from M. F. Hasler, Aug 23 2015