A103443 Largest left-truncatable prime in base n (decimal expansion).

23, 4091, 7817, 4836525320399, 817337, 14005650767869, 1676456897, 357686312646216567629137, 2276005673, 13092430647736190817303130065827539, 812751503, 615419590422100474355767356763

Offset

3,1

Links

Martin Fuller, Table of n, a(n) for n = 3..29

I. O. Angell, and H. J. Godwin, On Truncatable Primes Math. Comput. 31, 265-267, 1977. (See also Sloane link below)

James Grime and Brady Haran, 357686312646216567629137, Numberphile video (2018).

Martin Renner, Table of n, a(n) for n = 3..53 (with some question marks). Corrected and expanded by Hans Havermann, Jan 25 2014.

N. J. A. Sloane, The Angell-Godwin table of initial terms of A023107 and A103443

Eric Weisstein's World of Mathematics, Truncatable Prime.

Index entries for sequences related to truncatable primes

Prog

(PARI) a(n)=my(v=primes(primepi(n-1)), u, t, b=1, best); while(#v, best=vecmax(v); b*=n; u=List(); for(i=1, #v, for(k=1, n-1, if(isprime(t=v[i]+k*b), listput(u, t)))); v=Vec(u)); best \\ Charles R Greathouse IV, Feb 05 2013

Crossrefs

Cf. A076623, A023107, A103463, A254755.

Sequence in context: A368137 A352977 A308458 * A059000 A233235 A286706

Adjacent sequences: A103440 A103441 A103442 * A103444 A103445 A103446

Keyword

nonn,base

Author

Martin Renner, Mar 21 2005, Sep 24 2007, Apr 20 2008

Extensions

Base-14 entry corrected by Hans Havermann, May 30 2011

Corresponding entry in a-file corrected by N. J. A. Sloane, Jun 02 2011

a-file corrected and expanded by Hans Havermann, Jan 25 2014

Status

approved