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A103443 Largest left-truncatable prime in base n (decimal expansion). 8
23, 4091, 7817, 4836525320399, 817337, 14005650767869, 1676456897, 357686312646216567629137, 2276005673, 13092430647736190817303130065827539, 812751503, 615419590422100474355767356763 (list; graph; refs; listen; history; text; internal format)



Table of n, a(n) for n=3..14.

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


(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


Cf. A076623, A023107, A103463, A254755.

Sequence in context: A134798 A352977 A308458 * A059000 A233235 A286706

Adjacent sequences:  A103440 A103441 A103442 * A103444 A103445 A103446




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


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



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Last modified October 6 09:29 EDT 2022. Contains 357263 sequences. (Running on oeis4.)