A127890 Largest n-digit right-truncatable prime.

7, 79, 797, 7393, 73939, 739399, 7393933, 73939133

Offset

1,1

Comments

For a variant see the Howard reference. - Alexander R. Povolotsky, Dec 23 2007

Right-truncatable means that the integer part of successive divisions by 10 always yields primes (or zero). - M. F. Hasler, Nov 07 2018

References

Toby Howard, "Magic Pi - The Magic of Numbers", PC Advisor magazine, May 1998.

Links

Table of n, a(n) for n=1..8.

I. O. Angell and H. J. Godwin, On Truncatable Primes, Math. Comput. 31, 265-267, 1977.

Jens Fehlau, 73939133 - Probably the Most Interesting Prime Number [Part 1] and [Part 2], Flammable Maths videos (2020).

Index entries for sequences related to truncatable primes

Prog

(PARI) A127890=vector(8, n, p=concat(apply(t->primes([t, t+1]*10), if(n>1, p))); p[#p]) \\ M. F. Hasler, Nov 07 2018

Crossrefs

Cf. A024770, A050986, A127889.

Sequence in context: A104094 A220382 A036950 * A198973 A127859 A372969

Adjacent sequences: A127887 A127888 A127889 * A127891 A127892 A127893

Keyword

base,nonn,fini,full

Author

Ray Chandler, Feb 04 2007

Status

approved